diff --git a/Pipfile b/Pipfile
index fd49f661..3225341e 100644
--- a/Pipfile
+++ b/Pipfile
@@ -22,7 +22,7 @@ tox = "*"
 detox = "*"
 httpbin = "==0.5.0"
 pytest-mypy = "*"
-black = {version="*", python_version="=='3.6'"}
+white = {version="*"}
 "e1839a8" = {path = ".", editable = true, extras=["socks"]}
 mypy = "==0.540"
 
diff --git a/requests/__init__.py b/requests/__init__.py
index 0acbecbf..2435d503 100644
--- a/requests/__init__.py
+++ b/requests/__init__.py
@@ -46,7 +46,9 @@ from .exceptions import RequestsDependencyWarning
 
 def check_compatibility(urllib3_version: str, chardet_version: str) -> None:
     urllib3_version = urllib3_version.split('.')
-    assert urllib3_version != ['dev']  # Verify urllib3 isn't installed from git.
+    assert urllib3_version != [
+        'dev'
+    ]  # Verify urllib3 isn't installed from git.
     # Sometimes, urllib3 only reports its version as 16.1.
     if len(urllib3_version) == 2:
         urllib3_version.append('0')
diff --git a/requests/adapters.py b/requests/adapters.py
index c0dd2d30..fd6c9e3e 100644
--- a/requests/adapters.py
+++ b/requests/adapters.py
@@ -117,7 +117,8 @@ def _pool_kwargs(verify, cert):
 
         if key_file and not os.path.exists(key_file):
             raise IOError(
-                "Could not find the TLS key file, " "invalid path: {0}".format(key_file)
+                "Could not find the TLS key file, "
+                "invalid path: {0}".format(key_file)
             )
 
     return pool_kwargs
@@ -130,7 +131,13 @@ class BaseAdapter(object):
         super(BaseAdapter, self).__init__()
 
     def send(
-        self, request, stream=False, timeout=None, verify=True, cert=None, proxies=None
+        self,
+        request,
+        stream=False,
+        timeout=None,
+        verify=True,
+        cert=None,
+        proxies=None,
     ):
         """Sends PreparedRequest object. Returns Response object.
 
@@ -180,7 +187,11 @@ class HTTPAdapter(BaseAdapter):
       >>> s.mount('http://', a)
     """
     __attrs__ = [
-        'max_retries', 'config', '_pool_connections', '_pool_maxsize', '_pool_block'
+        'max_retries',
+        'config',
+        '_pool_connections',
+        '_pool_maxsize',
+        '_pool_block',
     ]
 
     def __init__(
@@ -323,12 +334,16 @@ class HTTPAdapter(BaseAdapter):
         if proxy:
             proxy = prepend_scheme_if_needed(proxy, 'http')
             proxy_manager = self.proxy_manager_for(proxy)
-            conn = proxy_manager.connection_from_url(url, pool_kwargs=pool_kwargs)
+            conn = proxy_manager.connection_from_url(
+                url, pool_kwargs=pool_kwargs
+            )
         else:
             # Only scheme should be lower case
             parsed = urlparse(url)
             url = parsed.geturl()
-            conn = self.poolmanager.connection_from_url(url, pool_kwargs=pool_kwargs)
+            conn = self.poolmanager.connection_from_url(
+                url, pool_kwargs=pool_kwargs
+            )
         return conn
 
     def close(self):
@@ -397,11 +412,19 @@ class HTTPAdapter(BaseAdapter):
         headers = {}
         username, password = get_auth_from_url(proxy)
         if username:
-            headers['Proxy-Authorization'] = _basic_auth_str(username, password)
+            headers['Proxy-Authorization'] = _basic_auth_str(
+                username, password
+            )
         return headers
 
     def send(
-        self, request, stream=False, timeout=None, verify=True, cert=None, proxies=None
+        self,
+        request,
+        stream=False,
+        timeout=None,
+        verify=True,
+        cert=None,
+        proxies=None,
     ):
         """Sends PreparedRequest object. Returns Response object.
 
@@ -421,7 +444,9 @@ class HTTPAdapter(BaseAdapter):
         conn = self.get_connection(request.url, proxies, verify, cert)
         url = self.request_url(request, proxies)
         self.add_headers(request)
-        chunked = not (request.body is None or 'Content-Length' in request.headers)
+        chunked = not (
+            request.body is None or 'Content-Length' in request.headers
+        )
         if isinstance(timeout, tuple):
             try:
                 connect, read = timeout
@@ -460,7 +485,9 @@ class HTTPAdapter(BaseAdapter):
                     conn = conn.proxy_pool
                 low_conn = conn._get_conn(timeout=DEFAULT_POOL_TIMEOUT)
                 try:
-                    low_conn.putrequest(request.method, url, skip_accept_encoding=True)
+                    low_conn.putrequest(
+                        request.method, url, skip_accept_encoding=True
+                    )
                     for header, value in request.headers.items():
                         low_conn.putheader(header, value)
                     low_conn.endheaders()
diff --git a/requests/api.py b/requests/api.py
index d2fe9150..cb7f4756 100644
--- a/requests/api.py
+++ b/requests/api.py
@@ -14,7 +14,11 @@ from .import types
 
 
 def request(
-    method: types.Method, url: types.URL, *, session: types.Session = None, **kwargs
+    method: types.Method,
+    url: types.URL,
+    *,
+    session: types.Session = None,
+    **kwargs,
 ) -> types.Response:
     """Constructs and sends a :class:`Request <Request>`.
 
@@ -61,7 +65,9 @@ def request(
         return session.request(method=method, url=url, **kwargs)
 
 
-def get(url: types.URL, *, params: types.Params = None, **kwargs) -> types.Response:
+def get(
+    url: types.URL, *, params: types.Params = None, **kwargs
+) -> types.Response:
     r"""Sends a GET request.
 
     :param url: URL for the new :class:`Request` object.
@@ -99,7 +105,11 @@ def head(url: types.URL, **kwargs) -> types.Response:
 
 
 def post(
-    url: types.URL, *, data: types.Data = None, json: types.JSON = None, **kwargs
+    url: types.URL,
+    *,
+    data: types.Data = None,
+    json: types.JSON = None,
+    **kwargs,
 ) -> types.Response:
     r"""Sends a POST request.
 
@@ -113,7 +123,9 @@ def post(
     return request('post', url, data=data, json=json, **kwargs)
 
 
-def put(url: types.URL, *, data: types.Data = None, **kwargs) -> types.Response:
+def put(
+    url: types.URL, *, data: types.Data = None, **kwargs
+) -> types.Response:
     r"""Sends a PUT request.
 
     :param url: URL for the new :class:`Request` object.
@@ -126,7 +138,9 @@ def put(url: types.URL, *, data: types.Data = None, **kwargs) -> types.Response:
     return request('put', url, data=data, **kwargs)
 
 
-def patch(url: types.URL, *, data: types.Data = None, **kwargs) -> types.Response:
+def patch(
+    url: types.URL, *, data: types.Data = None, **kwargs
+) -> types.Response:
     r"""Sends a PATCH request.
 
     :param url: URL for the new :class:`Request` object.
diff --git a/requests/auth.py b/requests/auth.py
index 7bcf359e..8e5a7510 100644
--- a/requests/auth.py
+++ b/requests/auth.py
@@ -73,7 +73,9 @@ class HTTPBasicAuth(AuthBase):
         return not self == other
 
     def __call__(self, r):
-        r.headers['Authorization'] = _basic_auth_str(self.username, self.password)
+        r.headers['Authorization'] = _basic_auth_str(
+            self.username, self.password
+        )
         return r
 
 
@@ -203,7 +205,9 @@ class HTTPDigestAuth(AuthBase):
         if 'digest' in s_auth.lower() and self._thread_local.num_401_calls < 2:
             self._thread_local.num_401_calls += 1
             pat = re.compile(r'digest ', flags=re.IGNORECASE)
-            self._thread_local.chal = parse_dict_header(pat.sub('', s_auth, count=1))
+            self._thread_local.chal = parse_dict_header(
+                pat.sub('', s_auth, count=1)
+            )
             # Consume content and release the original connection
             # to allow our new request to reuse the same one.
             r.content
@@ -227,7 +231,9 @@ class HTTPDigestAuth(AuthBase):
         self.init_per_thread_state()
         # If we have a saved nonce, skip the 401
         if self._thread_local.last_nonce:
-            r.headers['Authorization'] = self.build_digest_header(r.method, r.url)
+            r.headers['Authorization'] = self.build_digest_header(
+                r.method, r.url
+            )
         try:
             self._thread_local.pos = r.body.tell()
         except AttributeError:
diff --git a/requests/cookies.py b/requests/cookies.py
index adb61910..001d7e53 100644
--- a/requests/cookies.py
+++ b/requests/cookies.py
@@ -131,7 +131,9 @@ def extract_cookies_to_jar(jar, request, response):
     :param request: our own requests.Request object
     :param response: urllib3.HTTPResponse object
     """
-    if not (hasattr(response, '_original_response') and response._original_response):
+    if not (
+        hasattr(response, '_original_response') and response._original_response
+    ):
         return
 
     # the _original_response field is the wrapped httplib.HTTPResponse object,
@@ -218,7 +220,10 @@ class RequestsCookieJar(cookielib.CookieJar, collections.MutableMapping):
         # support client code that unsets cookies by assignment of a None value:
         if value is None:
             remove_cookie_by_name(
-                self, name, domain=kwargs.get('domain'), path=kwargs.get('path')
+                self,
+                name,
+                domain=kwargs.get('domain'),
+                path=kwargs.get('path'),
             )
             return
 
@@ -363,7 +368,9 @@ class RequestsCookieJar(cookielib.CookieJar, collections.MutableMapping):
             '"'
         ):
             cookie.value = cookie.value.replace('\\"', '')
-        return super(RequestsCookieJar, self).set_cookie(cookie, *args, **kwargs)
+        return super(RequestsCookieJar, self).set_cookie(
+            cookie, *args, **kwargs
+        )
 
     def update(self, other):
         """Updates this jar with cookies from another CookieJar or dict-like"""
@@ -412,7 +419,8 @@ class RequestsCookieJar(cookielib.CookieJar, collections.MutableMapping):
                     if path is None or cookie.path == path:
                         if toReturn is not None:  # if there are multiple cookies that meet passed in criteria
                             raise CookieConflictError(
-                                'There are multiple cookies with name, %r' % (name)
+                                'There are multiple cookies with name, %r' %
+                                (name)
                             )
 
                         toReturn = cookie.value  # we will eventually return this as long as no cookie conflict
@@ -502,7 +510,9 @@ def morsel_to_cookie(morsel):
 
     elif morsel['expires']:
         time_template = '%a, %d-%b-%Y %H:%M:%S GMT'
-        expires = calendar.timegm(time.strptime(morsel['expires'], time_template))
+        expires = calendar.timegm(
+            time.strptime(morsel['expires'], time_template)
+        )
     return create_cookie(
         comment=morsel['comment'],
         comment_url=bool(morsel['comment']),
@@ -548,7 +558,9 @@ def merge_cookies(cookiejar, cookies):
         raise ValueError('You can only merge into CookieJar')
 
     if isinstance(cookies, dict):
-        cookiejar = cookiejar_from_dict(cookies, cookiejar=cookiejar, overwrite=False)
+        cookiejar = cookiejar_from_dict(
+            cookies, cookiejar=cookiejar, overwrite=False
+        )
     elif isinstance(cookies, cookielib.CookieJar):
         try:
             cookiejar.update(cookies)
diff --git a/requests/exceptions.py b/requests/exceptions.py
index e4d3c366..4734c359 100644
--- a/requests/exceptions.py
+++ b/requests/exceptions.py
@@ -18,7 +18,11 @@ class RequestException(IOError):
         response = kwargs.pop('response', None)
         self.response = response
         self.request = kwargs.pop('request', None)
-        if (response is not None and not self.request and hasattr(response, 'request')):
+        if (
+            response is not None and
+            not self.request and
+            hasattr(response, 'request')
+        ):
             self.request = self.response.request
         super(RequestException, self).__init__(*args, **kwargs)
 
diff --git a/requests/help.py b/requests/help.py
index 6c299b34..68c80175 100644
--- a/requests/help.py
+++ b/requests/help.py
@@ -61,7 +61,9 @@ def _implementation() -> types.Help:
 def info() -> types.Help:
     """Generate information for a bug report."""
     try:
-        platform_info = {'system': platform.system(), 'release': platform.release()}
+        platform_info = {
+            'system': platform.system(), 'release': platform.release()
+        }
     except IOError:
         platform_info = {'system': 'Unknown', 'release': 'Unknown'}
     implementation_info = _implementation()
@@ -77,7 +79,9 @@ def info() -> types.Help:
     idna_info = {'version': getattr(idna, '__version__', '')}
     # OPENSSL_VERSION_NUMBER doesn't exist in the Python 2.6 ssl module.
     system_ssl = getattr(ssl, 'OPENSSL_VERSION_NUMBER', None)
-    system_ssl_info = {'version': '%x' % system_ssl if system_ssl is not None else ''}
+    system_ssl_info = {
+        'version': '%x' % system_ssl if system_ssl is not None else ''
+    }
     return {
         'platform': platform_info,
         'implementation': implementation_info,
diff --git a/requests/models.py b/requests/models.py
index 4bd0acef..02256f4d 100644
--- a/requests/models.py
+++ b/requests/models.py
@@ -458,7 +458,9 @@ class PreparedRequest(RequestEncodingMixin, RequestHooksMixin):
                 query = '%s&%s' % (query, enc_params)
             else:
                 query = enc_params
-        url = requote_uri(urlunparse([scheme, netloc, path, None, query, fragment]))
+        url = requote_uri(
+            urlunparse([scheme, netloc, path, None, query, fragment])
+        )
         self.url = url
 
     def prepare_headers(self, headers):
@@ -707,14 +709,18 @@ class Response(object):
         """True if this Response is a well-formed HTTP redirect that could have
         been processed automatically (by :meth:`Session.resolve_redirects`).
         """
-        return ('location' in self.headers and self.status_code in REDIRECT_STATI)
+        return (
+            'location' in self.headers and self.status_code in REDIRECT_STATI
+        )
 
     @property
     def is_permanent_redirect(self):
         """True if this Response one of the permanent versions of redirect."""
         return (
             'location' in self.headers and
-            self.status_code in (codes.moved_permanently, codes.permanent_redirect)
+            self.status_code in (
+                codes.moved_permanently, codes.permanent_redirect
+            )
         )
 
     @property
@@ -748,7 +754,9 @@ class Response(object):
             # Special case for urllib3.
             if hasattr(self.raw, 'stream'):
                 try:
-                    for chunk in self.raw.stream(chunk_size, decode_content=True):
+                    for chunk in self.raw.stream(
+                        chunk_size, decode_content=True
+                    ):
                         yield chunk
 
                 except ProtocolError as e:
@@ -780,7 +788,8 @@ class Response(object):
 
         elif chunk_size is not None and not isinstance(chunk_size, int):
             raise TypeError(
-                "chunk_size must be an int, it is instead a %s." % type(chunk_size)
+                "chunk_size must be an int, it is instead a %s." %
+                type(chunk_size)
             )
 
         # simulate reading small chunks of the content
@@ -790,7 +799,8 @@ class Response(object):
         if decode_unicode:
             if self.encoding is None:
                 raise TypeError(
-                    'encoding must be set before consuming streaming ' 'responses'
+                    'encoding must be set before consuming streaming '
+                    'responses'
                 )
 
             # check encoding value here, don't wait for the generator to be
@@ -880,7 +890,9 @@ class Response(object):
         if self._content is False:
             # Read the contents.
             if self._content_consumed:
-                raise RuntimeError('The content for this response was already consumed')
+                raise RuntimeError(
+                    'The content for this response was already consumed'
+                )
 
             if self.status_code == 0 or self.raw is None:
                 self._content = None
@@ -942,7 +954,9 @@ class Response(object):
             encoding = guess_json_utf(self.content)
             if encoding is not None:
                 try:
-                    return complexjson.loads(self.content.decode(encoding), **kwargs)
+                    return complexjson.loads(
+                        self.content.decode(encoding), **kwargs
+                    )
 
                 except UnicodeDecodeError:
                     # Wrong UTF codec detected; usually because it's not UTF-8
diff --git a/requests/sessions.py b/requests/sessions.py
index 477dbb11..a4ca2719 100644
--- a/requests/sessions.py
+++ b/requests/sessions.py
@@ -75,7 +75,8 @@ def merge_setting(request_setting, session_setting, dict_class=OrderedDict):
 
     # Bypass if not a dictionary (e.g. verify)
     if not (
-        isinstance(session_setting, Mapping) and isinstance(request_setting, Mapping)
+        isinstance(session_setting, Mapping) and
+        isinstance(request_setting, Mapping)
     ):
         return request_setting
 
@@ -166,7 +167,8 @@ class SessionRedirectMixin(object):
                 response.raw.read(decode_content=False)
             if len(response.history) >= self.max_redirects:
                 raise TooManyRedirects(
-                    'Exceeded %s redirects.' % self.max_redirects, response=response
+                    'Exceeded %s redirects.' % self.max_redirects,
+                    response=response,
                 )
 
             # Release the connection back into the pool.
@@ -193,7 +195,9 @@ class SessionRedirectMixin(object):
             # If method is changed to GET we need to remove body and associated headers.
             if method_changed and prepared_request.method == 'GET':
                 # https://github.com/requests/requests/issues/3490
-                purged_headers = ('Content-Length', 'Content-Type', 'Transfer-Encoding')
+                purged_headers = (
+                    'Content-Length', 'Content-Type', 'Transfer-Encoding'
+                )
                 for header in purged_headers:
                     prepared_request.headers.pop(header, None)
                 prepared_request.body = None
@@ -205,7 +209,9 @@ class SessionRedirectMixin(object):
             # Extract any cookies sent on the response to the cookiejar
             # in the new request. Because we've mutated our copied prepared
             # request, use the old one that we haven't yet touched.
-            extract_cookies_to_jar(prepared_request._cookies, request, response.raw)
+            extract_cookies_to_jar(
+                prepared_request._cookies, request, response.raw
+            )
             merge_cookies(prepared_request._cookies, self.cookies)
             prepared_request.prepare_cookies(prepared_request._cookies)
             # Rebuild auth and proxy information.
@@ -241,7 +247,9 @@ class SessionRedirectMixin(object):
                 response.history = history[:]
                 # append the new response to the history tracker for the next iteration
                 history.append(response)
-                extract_cookies_to_jar(self.cookies, prepared_request, response.raw)
+                extract_cookies_to_jar(
+                    self.cookies, prepared_request, response.raw
+                )
                 # extract redirect url, if any, for the next loop
                 location_url = self.get_redirect_target(response)
                 yield response
@@ -298,7 +306,9 @@ class SessionRedirectMixin(object):
         except KeyError:
             username, password = None, None
         if username and password:
-            headers['Proxy-Authorization'] = _basic_auth_str(username, password)
+            headers['Proxy-Authorization'] = _basic_auth_str(
+                username, password
+            )
         return new_proxies
 
     def rebuild_method(self, prepared_request, response):
@@ -317,7 +327,9 @@ class SessionRedirectMixin(object):
         # of HTTP RFCs. While some browsers transform other methods to GET, little of
         # that has been standardized. For that reason, we're using curl as a model
         # which only supports POST->GET.
-        if response.status_code in (codes.found, codes.moved) and method == 'POST':
+        if response.status_code in (
+            codes.found, codes.moved
+        ) and method == 'POST':
             method = 'GET'
         prepared_request.method = method
         return method != original_method
@@ -642,7 +654,9 @@ class Session(SessionRedirectMixin):
         if not allow_redirects:
             try:
                 r._next = next(
-                    self.resolve_redirects(r, request, yield_requests=True, **kwargs)
+                    self.resolve_redirects(
+                        r, request, yield_requests=True, **kwargs
+                    )
                 )
             except StopIteration:
                 pass
@@ -685,7 +699,12 @@ class Session(SessionRedirectMixin):
             env_proxies = get_environ_proxies(url, no_proxy=no_proxy) or {}
         new_proxies = merge_setting(self.proxies, env_proxies)
         proxies = merge_setting(proxies, new_proxies)
-        return {'verify': verify, 'proxies': proxies, 'stream': stream, 'cert': cert}
+        return {
+            'verify': verify,
+            'proxies': proxies,
+            'stream': stream,
+            'cert': cert,
+        }
 
     def get_adapter(self, url):
         """
diff --git a/requests/status_codes.py b/requests/status_codes.py
index 964cb8c3..30c4edc4 100644
--- a/requests/status_codes.py
+++ b/requests/status_codes.py
@@ -37,7 +37,9 @@ _codes = {
     404: ('not_found', '-o-'),
     405: ('method_not_allowed', 'not_allowed'),
     406: ('not_acceptable',),
-    407: ('proxy_authentication_required', 'proxy_auth', 'proxy_authentication'),
+    407: (
+        'proxy_authentication_required', 'proxy_auth', 'proxy_authentication'
+    ),
     408: ('request_timeout', 'timeout'),
     409: ('conflict',),
     410: ('gone',),
@@ -47,7 +49,9 @@ _codes = {
     414: ('request_uri_too_large',),
     415: ('unsupported_media_type', 'unsupported_media', 'media_type'),
     416: (
-        'requested_range_not_satisfiable', 'requested_range', 'range_not_satisfiable'
+        'requested_range_not_satisfiable',
+        'requested_range',
+        'range_not_satisfiable',
     ),
     417: ('expectation_failed',),
     418: ('im_a_teapot', 'teapot', 'i_am_a_teapot'),
@@ -76,7 +80,11 @@ _codes = {
     507: ('insufficient_storage',),
     509: ('bandwidth_limit_exceeded', 'bandwidth'),
     510: ('not_extended',),
-    511: ('network_authentication_required', 'network_auth', 'network_authentication'),
+    511: (
+        'network_authentication_required',
+        'network_auth',
+        'network_authentication',
+    ),
 }
 codes = LookupDict(name='status_codes')
 for code, titles in _codes.items():
diff --git a/requests/structures.py b/requests/structures.py
index c0b13c2b..fb56a100 100644
--- a/requests/structures.py
+++ b/requests/structures.py
@@ -61,7 +61,9 @@ class CaseInsensitiveDict(collections.MutableMapping):
 
     def lower_items(self):
         """Like iteritems(), but with all lowercase keys."""
-        return ((lowerkey, keyval[1]) for (lowerkey, keyval) in self._store.items())
+        return (
+            (lowerkey, keyval[1]) for (lowerkey, keyval) in self._store.items()
+        )
 
     def __eq__(self, other):
         if isinstance(other, collections.Mapping):
diff --git a/requests/types.py b/requests/types.py
index d432fb0d..ebddfb4a 100644
--- a/requests/types.py
+++ b/requests/types.py
@@ -50,7 +50,10 @@ Headers = Optional[Union[None, MutableMapping[Text, Text]]]
 Cookies = Optional[Union[None, RequestsCookieJar, MutableMapping[Text, Text]]]
 Files = Optional[MutableMapping[Text, IO]]
 Auth = Union[
-    None, Tuple[Text, Text], auth.AuthBase, Callable[[PreparedRequest], PreparedRequest]
+    None,
+    Tuple[Text, Text],
+    auth.AuthBase,
+    Callable[[PreparedRequest], PreparedRequest],
 ]
 Timeout = Union[None, float, Tuple[float, float]]
 AllowRedirects = Optional[bool]
diff --git a/requests/utils.py b/requests/utils.py
index 1099fa74..ec831ba0 100644
--- a/requests/utils.py
+++ b/requests/utils.py
@@ -58,8 +58,14 @@ if platform.system() == 'Windows':
                 winreg.HKEY_CURRENT_USER,
                 r'Software\Microsoft\Windows\CurrentVersion\Internet Settings',
             )
-            proxyEnable = winreg.QueryValueEx(internetSettings, 'ProxyEnable')[0]
-            proxyOverride = winreg.QueryValueEx(internetSettings, 'ProxyOverride')[0]
+            proxyEnable = winreg.QueryValueEx(internetSettings, 'ProxyEnable')[
+                0
+            ]
+            proxyOverride = winreg.QueryValueEx(
+                internetSettings, 'ProxyOverride'
+            )[
+                0
+            ]
         except OSError:
             return False
 
@@ -210,7 +216,12 @@ def get_netrc_auth(url, raise_errors=False):
 def guess_filename(obj):
     """Tries to guess the filename of the given object."""
     name = getattr(obj, 'name', None)
-    if (name and isinstance(name, basestring) and name[0] != '<' and name[-1] != '>'):
+    if (
+        name and
+        isinstance(name, basestring) and
+        name[0] != '<' and
+        name[-1] != '>'
+    ):
         return os.path.basename(name)
 
 
@@ -401,7 +412,9 @@ def get_encodings_from_content(content):
         DeprecationWarning,
     )
     charset_re = re.compile(r'<meta.*?charset=["\']*(.+?)["\'>]', flags=re.I)
-    pragma_re = re.compile(r'<meta.*?content=["\']*;?charset=(.+?)["\'>]', flags=re.I)
+    pragma_re = re.compile(
+        r'<meta.*?content=["\']*;?charset=(.+?)["\'>]', flags=re.I
+    )
     xml_re = re.compile(r'^<\?xml.*?encoding=["\']*(.+?)["\'>]')
     return (
         charset_re.findall(content) +
@@ -570,7 +583,9 @@ def address_in_network(ip, net):
     """
     ipaddr = struct.unpack('=L', socket.inet_aton(ip))[0]
     netaddr, bits = net.split('/')
-    netmask = struct.unpack('=L', socket.inet_aton(dotted_netmask(int(bits))))[0]
+    netmask = struct.unpack('=L', socket.inet_aton(dotted_netmask(int(bits))))[
+        0
+    ]
     network = struct.unpack('=L', socket.inet_aton(netaddr))[0] & netmask
     return ( ipaddr & netmask) == ( network & netmask)
 
@@ -663,7 +678,9 @@ def should_bypass_proxies(url, no_proxy):
     if no_proxy:
         # We need to check whether we match here. We need to see if we match
         # the end of the netloc, both with and without the port.
-        no_proxy = (host for host in no_proxy.replace(' ', '').split(',') if host)
+        no_proxy = (
+            host for host in no_proxy.replace(' ', '').split(',') if host
+        )
         ip = netloc.split(':')[0]
         if is_ipv4_address(ip):
             for proxy_ip in no_proxy:
@@ -678,7 +695,9 @@ def should_bypass_proxies(url, no_proxy):
 
         else:
             for host in no_proxy:
-                if netloc.endswith(host) or netloc.split(':')[0].endswith(host):
+                if netloc.endswith(host) or netloc.split(':')[0].endswith(
+                    host
+                ):
                     # The URL does match something in no_proxy, so we don't want
                     # to apply the proxies on this URL.
                     return True
@@ -888,7 +907,8 @@ def check_header_validity(header):
     try:
         if not pat.match(value):
             raise InvalidHeader(
-                "Invalid return character or leading space in header: %s" % name
+                "Invalid return character or leading space in header: %s" %
+                name
             )
 
     except TypeError:
@@ -924,15 +944,20 @@ def rewind_body(prepared_request):
             body_seek(prepared_request._body_position)
         except (IOError, OSError):
             raise UnrewindableBodyError(
-                "An error occurred when rewinding request " "body for redirect."
+                "An error occurred when rewinding request "
+                "body for redirect."
             )
 
     else:
-        raise UnrewindableBodyError("Unable to rewind request body for redirect.")
+        raise UnrewindableBodyError(
+            "Unable to rewind request body for redirect."
+        )
 
 
 def is_stream(data):
     """Given data, determines if it should be sent as a stream."""
     is_iterable = getattr(data, '__iter__', False)
-    is_io_type = not isinstance(data, (basestring, list, tuple, collections.Mapping))
+    is_io_type = not isinstance(
+        data, (basestring, list, tuple, collections.Mapping)
+    )
     return is_iterable and is_io_type
diff --git a/setup.py b/setup.py
index e7bbd228..aa8b13dd 100755
--- a/setup.py
+++ b/setup.py
@@ -111,6 +111,8 @@ setup(
     extras_require={
         'security': ['pyOpenSSL>=0.14', 'cryptography>=1.3.4', 'idna>=2.0.0'],
         'socks': ['PySocks>=1.5.6, !=1.5.7'],
-        'socks:sys_platform == "win32" and python_version == "2.7"': ['win_inet_pton'],
+        'socks:sys_platform == "win32" and python_version == "2.7"': [
+            'win_inet_pton'
+        ],
     },
 )
diff --git a/tests/test_help.py b/tests/test_help.py
index a61c9ebd..7863eb60 100644
--- a/tests/test_help.py
+++ b/tests/test_help.py
@@ -6,7 +6,9 @@ import pytest
 from requests.help import info
 
 
-@pytest.mark.skipif(sys.version_info[:2] != (2, 6), reason="Only run on Python 2.6")
+@pytest.mark.skipif(
+    sys.version_info[:2] != (2, 6), reason="Only run on Python 2.6"
+)
 def test_system_ssl_py26():
     """OPENSSL_VERSION_NUMBER isn't provided in Python 2.6, verify we don't
     blow up in this case.
@@ -14,7 +16,9 @@ def test_system_ssl_py26():
     assert info()['system_ssl'] == {'version': ''}
 
 
-@pytest.mark.skipif(sys.version_info < (2, 7), reason="Only run on Python 2.7+")
+@pytest.mark.skipif(
+    sys.version_info < (2, 7), reason="Only run on Python 2.7+"
+)
 def test_system_ssl():
     """Verify we're actually setting system_ssl when it should be available."""
     assert info()['system_ssl']['version'] != ''
diff --git a/tests/test_hooks.py b/tests/test_hooks.py
index 126ec97d..a5167e40 100644
--- a/tests/test_hooks.py
+++ b/tests/test_hooks.py
@@ -12,7 +12,9 @@ def hook(value):
     'hooks_list, result', ((hook, 'ata'), ([hook, lambda x: None, hook], 'ta'))
 )
 def test_hooks(hooks_list, result):
-    assert hooks.dispatch_hook('response', {'response': hooks_list}, 'Data') == result
+    assert hooks.dispatch_hook(
+        'response', {'response': hooks_list}, 'Data'
+    ) == result
 
 
 def test_default_hooks():
diff --git a/tests/test_lowlevel.py b/tests/test_lowlevel.py
index c02f2b8f..1249332b 100644
--- a/tests/test_lowlevel.py
+++ b/tests/test_lowlevel.py
@@ -51,7 +51,9 @@ def test_digestauth_401_count_reset_on_redirect():
         b'realm="me@kennethreitz.com", qop=auth\r\n\r\n'
     )
     text_302 = (
-        b'HTTP/1.1 302 FOUND\r\n' b'Content-Length: 0\r\n' b'Location: /\r\n\r\n'
+        b'HTTP/1.1 302 FOUND\r\n'
+        b'Content-Length: 0\r\n'
+        b'Location: /\r\n\r\n'
     )
     text_200 = (b'HTTP/1.1 200 OK\r\n' b'Content-Length: 0\r\n\r\n')
     expected_digest = (
@@ -130,7 +132,9 @@ def test_digestauth_401_only_sent_once():
         return request_content
 
     close_server = threading.Event()
-    server = Server(digest_failed_response_handler, wait_to_close_event=close_server)
+    server = Server(
+        digest_failed_response_handler, wait_to_close_event=close_server
+    )
     with server as (host, port):
         url = 'http://{0}:{1}/'.format(host, port)
         r = requests.get(url, auth=auth)
@@ -188,7 +192,8 @@ _proxy_combos += [(var.upper(), scheme) for var, scheme in _proxy_combos]
 @pytest.mark.parametrize("var,scheme", _proxy_combos)
 def test_use_proxy_from_environment(httpbin, var, scheme):
     url = "{0}://httpbin.org".format(scheme)
-    fake_proxy = Server()  # do nothing with the requests; just close the socket
+    fake_proxy = Server(
+    )  # do nothing with the requests; just close the socket
     with fake_proxy as (host, port):
         proxy_url = "socks5://{0}:{1}".format(host, port)
         kwargs = {var: proxy_url}
@@ -227,6 +232,8 @@ def test_redirect_rfc1808_to_non_ascii_location():
         assert r.status_code == 200
         assert len(r.history) == 1
         assert r.history[0].status_code == 301
-        assert redirect_request[0].startswith(b'GET /' + expected_path + b' HTTP/1.1')
+        assert redirect_request[0].startswith(
+            b'GET /' + expected_path + b' HTTP/1.1'
+        )
         assert r.url == u'{0}/{1}'.format(url, expected_path.decode('ascii'))
         close_server.set()
diff --git a/tests/test_requests.py b/tests/test_requests.py
index 5e5ae666..44f8e358 100644
--- a/tests/test_requests.py
+++ b/tests/test_requests.py
@@ -15,7 +15,9 @@ import pytest
 import pytest_httpbin
 from requests.adapters import HTTPAdapter
 from requests.auth import HTTPDigestAuth, _basic_auth_str
-from requests.basics import ( Morsel, cookielib, getproxies, str, urlparse, builtin_str)
+from requests.basics import (
+    Morsel, cookielib, getproxies, str, urlparse, builtin_str
+)
 from requests.cookies import ( cookiejar_from_dict, morsel_to_cookie)
 from requests.exceptions import (
     ConnectionError,
@@ -123,17 +125,24 @@ class TestRequests:
 
     @pytest.mark.parametrize('method', ('POST', 'PUT', 'PATCH', 'OPTIONS'))
     def test_empty_content_length(self, httpbin, method):
-        req = requests.Request(method, httpbin(method.lower()), data='').prepare()
+        req = requests.Request(
+            method, httpbin(method.lower()), data=''
+        ).prepare(
+        )
         assert req.headers['Content-Length'] == '0'
 
     def test_override_content_length(self, httpbin):
         headers = {'Content-Length': 'not zero'}
-        r = requests.Request('POST', httpbin('post'), headers=headers).prepare()
+        r = requests.Request('POST', httpbin('post'), headers=headers).prepare(
+        )
         assert 'Content-Length' in r.headers
         assert r.headers['Content-Length'] == 'not zero'
 
     def test_path_is_not_double_encoded(self):
-        request = requests.Request('GET', "http://0.0.0.0/get/test case").prepare()
+        request = requests.Request(
+            'GET', "http://0.0.0.0/get/test case"
+        ).prepare(
+        )
         assert request.path_url == '/get/test%20case'
 
     @pytest.mark.parametrize(
@@ -183,7 +192,9 @@ class TestRequests:
         request = requests.Request('GET', ' http://example.com').prepare()
         assert request.url == 'http://example.com/'
 
-    @pytest.mark.parametrize('scheme', ('http://', 'HTTP://', 'hTTp://', 'HttP://'))
+    @pytest.mark.parametrize(
+        'scheme', ('http://', 'HTTP://', 'hTTp://', 'HttP://')
+    )
     def test_mixed_case_scheme_acceptable(self, httpbin, scheme):
         s = requests.Session()
         s.proxies = getproxies()
@@ -238,7 +249,9 @@ class TestRequests:
             assert e.response.url == url
             assert len(e.response.history) == 30
         else:
-            pytest.fail('Expected redirect to raise TooManyRedirects but it did not')
+            pytest.fail(
+                'Expected redirect to raise TooManyRedirects but it did not'
+            )
 
     def test_HTTP_302_TOO_MANY_REDIRECTS_WITH_PARAMS(self, httpbin):
         s = requests.session()
@@ -266,7 +279,9 @@ class TestRequests:
             ('DELETE', '', 'DELETE'),
         ),
     )
-    def test_http_301_for_redirectable_methods(self, httpbin, method, body, expected):
+    def test_http_301_for_redirectable_methods(
+        self, httpbin, method, body, expected
+    ):
         """Tests all methods except OPTIONS for expected redirect behaviour.
 
         OPTIONS responses can behave differently depending on the server, so
@@ -274,7 +289,9 @@ class TestRequests:
         to them. For that reason they aren't included here.
         """
         params = {'url': '/%s' % expected.lower(), 'status_code': '301'}
-        r = requests.request(method, httpbin('redirect-to'), data=body, params=params)
+        r = requests.request(
+            method, httpbin('redirect-to'), data=body, params=params
+        )
         assert r.request.url == httpbin(expected.lower())
         assert r.request.method == expected
         assert r.history[0].status_code == 301
@@ -295,7 +312,9 @@ class TestRequests:
             ('DELETE', '', 'DELETE'),
         ),
     )
-    def test_http_302_for_redirectable_methods(self, httpbin, method, body, expected):
+    def test_http_302_for_redirectable_methods(
+        self, httpbin, method, body, expected
+    ):
         """Tests all methods except OPTIONS for expected redirect behaviour.
 
         OPTIONS responses can behave differently depending on the server, so
@@ -303,7 +322,9 @@ class TestRequests:
         to them. For that reason they aren't included here.
         """
         params = {'url': '/%s' % expected.lower()}
-        r = requests.request(method, httpbin('redirect-to'), data=body, params=params)
+        r = requests.request(
+            method, httpbin('redirect-to'), data=body, params=params
+        )
         assert r.request.url == httpbin(expected.lower())
         assert r.request.method == expected
         assert r.history[0].status_code == 302
@@ -324,7 +345,9 @@ class TestRequests:
             ('DELETE', '', 'GET'),
         ),
     )
-    def test_http_303_for_redirectable_methods(self, httpbin, method, body, expected):
+    def test_http_303_for_redirectable_methods(
+        self, httpbin, method, body, expected
+    ):
         """Tests all methods except OPTIONS for expected redirect behaviour.
 
         OPTIONS responses can behave differently depending on the server, so
@@ -332,7 +355,9 @@ class TestRequests:
         to them. For that reason they aren't included here.
         """
         params = {'url': '/%s' % expected.lower(), 'status_code': '303'}
-        r = requests.request(method, httpbin('redirect-to'), data=body, params=params)
+        r = requests.request(
+            method, httpbin('redirect-to'), data=body, params=params
+        )
         assert r.request.url == httpbin(expected.lower())
         assert r.request.method == expected
         assert r.history[0].status_code == 303
@@ -341,7 +366,8 @@ class TestRequests:
 
     def test_multiple_location_headers(self, httpbin):
         headers = [
-            ('Location', 'http://example.com'), ('Location', 'https://example.com/1')
+            ('Location', 'http://example.com'),
+            ('Location', 'https://example.com/1'),
         ]
         params = '&'.join(['%s=%s' % (k, v) for k, v in headers])
         ses = requests.Session()
@@ -372,7 +398,9 @@ class TestRequests:
     def test_transfer_enc_removal_on_redirect(self, httpbin):
         purged_headers = ('Transfer-Encoding', 'Content-Type')
         ses = requests.Session()
-        req = requests.Request('POST', httpbin('post'), data=(b'x' for x in range(1)))
+        req = requests.Request(
+            'POST', httpbin('post'), data=(b'x' for x in range(1))
+        )
         prep = ses.prepare_request(req)
         assert 'Transfer-Encoding' in prep.headers
         # Create Response to avoid https://github.com/kevin1024/pytest-httpbin/issues/33
@@ -420,7 +448,9 @@ class TestRequests:
         assert s.cookies['foo'] == 'bar'
         s.get(
             httpbin('response-headers'),
-            params={'Set-Cookie': 'foo=deleted; expires=Thu, 01-Jan-1970 00:00:01 GMT'},
+            params={
+                'Set-Cookie': 'foo=deleted; expires=Thu, 01-Jan-1970 00:00:01 GMT'
+            },
         )
         assert 'foo' not in s.cookies
 
@@ -489,7 +519,9 @@ class TestRequests:
         # Verify CookieJar isn't being converted to RequestsCookieJar
         assert isinstance(prep_req._cookies, cookielib.CookieJar)
         assert isinstance(resp.request._cookies, cookielib.CookieJar)
-        assert not isinstance(resp.request._cookies, requests.cookies.RequestsCookieJar)
+        assert not isinstance(
+            resp.request._cookies, requests.cookies.RequestsCookieJar
+        )
         cookies = {}
         for c in resp.request._cookies:
             cookies[c.name] = c.value
@@ -594,16 +626,23 @@ class TestRequests:
 
     @pytest.mark.parametrize(
         'username, password',
-        (('user', 'pass'), (u'имя'.encode('utf-8'), u'пароль'.encode('utf-8'))),
+        (
+            ('user', 'pass'),
+            (u'имя'.encode('utf-8'), u'пароль'.encode('utf-8')),
+        ),
     )
     def test_set_basicauth(self, httpbin, username, password):
         auth = (username, password)
         url = httpbin('get')
         r = requests.Request('GET', url, auth=auth)
         p = r.prepare()
-        assert p.headers['Authorization'] == _basic_auth_str(username, password)
+        assert p.headers['Authorization'] == _basic_auth_str(
+            username, password
+        )
 
-    @pytest.mark.parametrize('username, password', (('user', 1234), (None, 'test')))
+    @pytest.mark.parametrize(
+        'username, password', (('user', 1234), (None, 'test'))
+    )
     def test_non_str_basicauth(self, username, password):
         """Ensure we only allow string or bytes values for basicauth"""
         with pytest.raises(TypeError) as e:
@@ -634,7 +673,8 @@ class TestRequests:
         # any proxy related error (address resolution, no route to host, etc) should result in a ProxyError
         with pytest.raises(ProxyError):
             requests.get(
-                'http://localhost:1', proxies={'http': 'non-resolvable-address'}
+                'http://localhost:1',
+                proxies={'http': 'non-resolvable-address'},
             )
 
     def test_basicauth_with_netrc(self, httpbin):
@@ -779,7 +819,9 @@ class TestRequests:
         post1 = requests.post(url, data={'some': 'data'})
         assert post1.status_code == 200
         with open('Pipfile') as f:
-            post2 = requests.post(url, data={'some': 'data'}, files={'some': f})
+            post2 = requests.post(
+                url, data={'some': 'data'}, files={'some': f}
+            )
         assert post2.status_code == 200
         post4 = requests.post(url, data='[{"some": "json"}]')
         assert post4.status_code == 200
@@ -904,17 +946,23 @@ class TestRequests:
             warnings_expected = ('SubjectAltNameWarning',)
         else:
             warnings_expected = (
-                'SNIMissingWarning', 'InsecurePlatformWarning', 'SubjectAltNameWarning'
+                'SNIMissingWarning',
+                'InsecurePlatformWarning',
+                'SubjectAltNameWarning',
             )
         with pytest.warns(None) as warning_records:
             warnings.simplefilter('always')
-            requests.get(httpbin_secure('status', '200'), verify=httpbin_ca_bundle)
+            requests.get(
+                httpbin_secure('status', '200'), verify=httpbin_ca_bundle
+            )
         warning_records = [
             item
             for item in warning_records
             if item.category.__name__ != 'ResourceWarning'
         ]
-        warnings_category = tuple(item.category.__name__ for item in warning_records)
+        warnings_category = tuple(
+            item.category.__name__ for item in warning_records
+        )
         assert warnings_category == warnings_expected
 
     def test_certificate_failure(self, httpbin_secure):
@@ -971,7 +1019,9 @@ class TestRequests:
 
     def test_unicode_method_name(self, httpbin):
         files = {'file': open(__file__, 'rb')}
-        r = requests.request(method=u('POST'), url=httpbin('post'), files=files)
+        r = requests.request(
+            method=u('POST'), url=httpbin('post'), files=files
+        )
         assert r.status_code == 200
 
     def test_unicode_method_name_with_request_object(self, httpbin):
@@ -998,7 +1048,9 @@ class TestRequests:
             files={
                 'file1': ('test_requests.py', open(__file__, 'rb')),
                 'file2': (
-                    'test_requests', open(__file__, 'rb'), 'text/py-content-type'
+                    'test_requests',
+                    open(__file__, 'rb'),
+                    'text/py-content-type',
                 ),
             },
         )
@@ -1062,7 +1114,9 @@ class TestRequests:
         s.auth = DummyAuth()
         prep = s.prepare_request(req)
         resp = s.send(prep)
-        assert resp.json()['headers']['Dummy-Auth-Test'] == 'dummy-auth-test-ok'
+        assert resp.json()['headers'][
+            'Dummy-Auth-Test'
+        ] == 'dummy-auth-test-ok'
 
     def test_prepare_request_with_bytestring_url(self):
         req = requests.Request('GET', b'https://httpbin.org/')
@@ -1223,7 +1277,9 @@ class TestRequests:
         r = requests.get(httpbin('get'))
         td = r.elapsed
         total_seconds = (
-            (td.microseconds + (td.seconds + td.days * 24 * 3600) * 10 ** 6) / 10 ** 6
+            (td.microseconds + (td.seconds + td.days * 24 * 3600) * 10 ** 6) /
+            10 **
+            6
         )
         assert total_seconds > 0.0
 
@@ -1262,7 +1318,8 @@ class TestRequests:
         assert all(isinstance(chunk, str) for chunk in chunks)
 
     @pytest.mark.parametrize(
-        'encoding, exception', ((None, TypeError), ('invalid encoding', LookupError))
+        'encoding, exception',
+        ((None, TypeError), ('invalid encoding', LookupError)),
     )
     def test_decode_unicode_encoding(self, encoding, exception):
         # raise an exception if encoding isn't set
@@ -1352,7 +1409,9 @@ class TestRequests:
         r._content_consumed = True
         r.iter_content = mock_iter_content
         # decode_unicode=None, output raw bytes
-        assert list(r.iter_lines(delimiter=b'\r\n')) == mock_data.split(b'\r\n')
+        assert list(r.iter_lines(delimiter=b'\r\n')) == mock_data.split(
+            b'\r\n'
+        )
         # decode_unicode=True, output unicode strings
         assert list(
             r.iter_lines(decode_unicode=True, delimiter=u'\r\n')
@@ -1375,7 +1434,10 @@ class TestRequests:
         assert list(r.iter_lines()) == mock_data.splitlines()
         # decode_unicode=True, output unicode strings
         unicode_mock_data = mock_data.decode('utf-8')
-        assert list(r.iter_lines(decode_unicode=True)) == unicode_mock_data.splitlines()
+        assert list(
+            r.iter_lines(decode_unicode=True)
+        ) == unicode_mock_data.splitlines(
+        )
 
     @pytest.mark.parametrize(
         'content, expected_no_delimiter, expected_delimiter',
@@ -1568,7 +1630,10 @@ class TestRequests:
     def test_header_validation(self, httpbin):
         """Ensure prepare_headers regex isn't flagging valid header contents."""
         headers_ok = {
-            'foo': 'bar baz qux', 'bar': u'fbbq'.encode('utf8'), 'baz': '', 'qux': '1'
+            'foo': 'bar baz qux',
+            'bar': u'fbbq'.encode('utf8'),
+            'baz': '',
+            'qux': '1',
         }
         r = requests.get(httpbin('get'), headers=headers_ok)
         assert r.request.headers['foo'] == headers_ok['foo']
@@ -1693,13 +1758,19 @@ class TestRequests:
     def test_prepare_body_position_non_stream(self):
         data = b'the data'
         s = requests.Session()
-        prep = requests.Request('GET', 'http://example.com', data=data).prepare()
+        prep = requests.Request(
+            'GET', 'http://example.com', data=data
+        ).prepare(
+        )
         assert prep._body_position is None
 
     def test_rewind_body(self):
         data = io.BytesIO(b'the data')
         s = requests.Session()
-        prep = requests.Request('GET', 'http://example.com', data=data).prepare()
+        prep = requests.Request(
+            'GET', 'http://example.com', data=data
+        ).prepare(
+        )
         assert prep._body_position == 0
         assert prep.body.read() == b'the data'
         # the data has all been read
@@ -1712,7 +1783,10 @@ class TestRequests:
         data = io.BytesIO(b'the data')
         s = requests.Session()
         data.read(4)  # read some data
-        prep = requests.Request('GET', 'http://example.com', data=data).prepare()
+        prep = requests.Request(
+            'GET', 'http://example.com', data=data
+        ).prepare(
+        )
         assert prep._body_position == 4
         assert prep.body.read() == b'data'
         # the data has all been read
@@ -1736,7 +1810,10 @@ class TestRequests:
 
         data = BadFileObj('the data')
         s = requests.Session()
-        prep = requests.Request('GET', 'http://example.com', data=data).prepare()
+        prep = requests.Request(
+            'GET', 'http://example.com', data=data
+        ).prepare(
+        )
         assert prep._body_position == 0
         with pytest.raises(UnrewindableBodyError) as e:
             requests.utils.rewind_body(prep)
@@ -1760,7 +1837,10 @@ class TestRequests:
 
         data = BadFileObj('the data')
         s = requests.Session()
-        prep = requests.Request('GET', 'http://example.com', data=data).prepare()
+        prep = requests.Request(
+            'GET', 'http://example.com', data=data
+        ).prepare(
+        )
         assert prep._body_position == 0
         with pytest.raises(UnrewindableBodyError) as e:
             requests.utils.rewind_body(prep)
@@ -1781,7 +1861,10 @@ class TestRequests:
 
         data = BadFileObj('the data')
         s = requests.Session()
-        prep = requests.Request('GET', 'http://example.com', data=data).prepare()
+        prep = requests.Request(
+            'GET', 'http://example.com', data=data
+        ).prepare(
+        )
         assert prep._body_position is not None
         with pytest.raises(UnrewindableBodyError) as e:
             requests.utils.rewind_body(prep)
@@ -1818,7 +1901,9 @@ class TestRequests:
             ),
         ),
     )
-    def test_basic_auth_str_is_always_native(self, username, password, auth_str):
+    def test_basic_auth_str_is_always_native(
+        self, username, password, auth_str
+    ):
         s = _basic_auth_str(username, password)
         assert isinstance(s, builtin_str)
         assert s == auth_str
@@ -1863,7 +1948,9 @@ class TestRequests:
 
     def test_unconsumed_session_response_closes_connection(self, httpbin):
         s = requests.session()
-        with contextlib.closing(s.get(httpbin('stream/4'), stream=True)) as response:
+        with contextlib.closing(
+            s.get(httpbin('stream/4'), stream=True)
+        ) as response:
             pass
         assert response._content_consumed is False
         assert response.raw.closed
@@ -1987,7 +2074,9 @@ class TestRequests:
         assert resp_with_cert.raw._pool.key_file == key
         assert resp.raw._pool is not resp_with_cert.raw._pool
 
-    def test_empty_stream_with_auth_does_not_set_content_length_header(self, httpbin):
+    def test_empty_stream_with_auth_does_not_set_content_length_header(
+        self, httpbin
+    ):
         """Ensure that a byte stream with size 0 will not set both a Content-Length
         and Transfer-Encoding header.
         """
@@ -1999,7 +2088,9 @@ class TestRequests:
         assert 'Transfer-Encoding' in prepared_request.headers
         assert 'Content-Length' not in prepared_request.headers
 
-    def test_stream_with_auth_does_not_set_transfer_encoding_header(self, httpbin):
+    def test_stream_with_auth_does_not_set_transfer_encoding_header(
+        self, httpbin
+    ):
         """Ensure that a byte stream with size > 0 will not set both a Content-Length
         and Transfer-Encoding header.
         """
@@ -2031,7 +2122,9 @@ class TestRequests:
         data = (i for i in [b'a', b'b', b'c'])
         url = httpbin('post')
         with pytest.raises(InvalidHeader):
-            r = requests.post(url, data=data, headers={'Content-Length': 'foo'})
+            r = requests.post(
+                url, data=data, headers={'Content-Length': 'foo'}
+            )
 
     def test_content_length_with_manually_set_transfer_encoding_raises_error(
         self, httpbin
@@ -2042,7 +2135,9 @@ class TestRequests:
         data = 'test data'
         url = httpbin('post')
         with pytest.raises(InvalidHeader):
-            r = requests.post(url, data=data, headers={'Transfer-Encoding': 'chunked'})
+            r = requests.post(
+                url, data=data, headers={'Transfer-Encoding': 'chunked'}
+            )
 
     def test_null_body_does_not_raise_error(self, httpbin):
         url = httpbin('post')
@@ -2095,7 +2190,9 @@ class TestRequests:
         """
         url_final = httpbin('html')
         querystring_malformed = urlencode({'location': url_final})
-        url_redirect_malformed = httpbin('response-headers?%s' % querystring_malformed)
+        url_redirect_malformed = httpbin(
+            'response-headers?%s' % querystring_malformed
+        )
         querystring_redirect = urlencode({'url': url_redirect_malformed})
         url_redirect = httpbin('redirect-to?%s' % querystring_redirect)
         urls_test = [url_redirect, url_redirect_malformed, url_final]
@@ -2333,14 +2430,19 @@ class TestTimeout:
 
     @pytest.mark.parametrize(
         'timeout, error_text',
-        (((3, 4, 5), '(connect, read)'), ('foo', 'must be an int, float or None')),
+        (
+            ((3, 4, 5), '(connect, read)'),
+            ('foo', 'must be an int, float or None'),
+        ),
     )
     def test_invalid_timeout(self, httpbin, timeout, error_text):
         with pytest.raises(ValueError) as e:
             requests.get(httpbin('get'), timeout=timeout)
         assert error_text in str(e)
 
-    @pytest.mark.parametrize('timeout', (None, Urllib3Timeout(connect=None, read=None)))
+    @pytest.mark.parametrize(
+        'timeout', (None, Urllib3Timeout(connect=None, read=None))
+    )
     def test_none_timeout(self, httpbin, timeout):
         """Check that you can set None as a valid timeout value.
 
@@ -2489,7 +2591,10 @@ def test_data_argument_accepts_tuples(data):
     """
     p = PreparedRequest()
     p.prepare(
-        method='GET', url='http://www.example.com', data=data, hooks=default_hooks()
+        method='GET',
+        url='http://www.example.com',
+        data=data,
+        hooks=default_hooks(),
     )
     assert p.body == urlencode(data)
 
@@ -2536,7 +2641,10 @@ def test_urllib3_retries(httpbin):
     from urllib3.util import Retry
 
     s = requests.Session()
-    s.mount('http://', HTTPAdapter(max_retries=Retry(total=2, status_forcelist=[500])))
+    s.mount(
+        'http://',
+        HTTPAdapter(max_retries=Retry(total=2, status_forcelist=[500])),
+    )
     with pytest.raises(RetryError):
         s.get(httpbin('status/500'))
 
@@ -2558,8 +2666,14 @@ class TestPreparingURLs(object):
             ('http://google.com', 'http://google.com/'),
             (u'http://ジェーピーニック.jp', u'http://xn--hckqz9bzb1cyrb.jp/'),
             (u'http://xn--n3h.net/', u'http://xn--n3h.net/'),
-            (u'http://ジェーピーニック.jp'.encode('utf-8'), u'http://xn--hckqz9bzb1cyrb.jp/'),
-            (u'http://straße.de/straße', u'http://xn--strae-oqa.de/stra%C3%9Fe'),
+            (
+                u'http://ジェーピーニック.jp'.encode('utf-8'),
+                u'http://xn--hckqz9bzb1cyrb.jp/',
+            ),
+            (
+                u'http://straße.de/straße',
+                u'http://xn--strae-oqa.de/stra%C3%9Fe',
+            ),
             (
                 u'http://straße.de/straße'.encode('utf-8'),
                 u'http://xn--strae-oqa.de/stra%C3%9Fe',
@@ -2643,8 +2757,16 @@ class TestPreparingURLs(object):
                 {"key": "value"},
                 u"http+unix://%2Fvar%2Frun%2Fsocket/path?key=value",
             ),
-            (b"mailto:user@example.org", {"key": "value"}, u"mailto:user@example.org"),
-            (u"mailto:user@example.org", {"key": "value"}, u"mailto:user@example.org"),
+            (
+                b"mailto:user@example.org",
+                {"key": "value"},
+                u"mailto:user@example.org",
+            ),
+            (
+                u"mailto:user@example.org",
+                {"key": "value"},
+                u"mailto:user@example.org",
+            ),
         ),
     )
     def test_parameters_for_nonstandard_schemes(self, input, params, expected):
@@ -2867,5 +2989,7 @@ class TestGetConnection(object):
         """
         adapter = requests.adapters.HTTPAdapter()
         with pytest.raises(IOError) as excinfo:
-            adapter.get_connection('https://example.com', verify=verify, cert=cert)
+            adapter.get_connection(
+                'https://example.com', verify=verify, cert=cert
+            )
         excinfo.match('invalid path: a/path/that/does/not/exist')
diff --git a/tests/test_structures.py b/tests/test_structures.py
index f1cbfb98..7d92516b 100644
--- a/tests/test_structures.py
+++ b/tests/test_structures.py
@@ -34,7 +34,9 @@ class TestCaseInsensitiveDict:
         ]
 
     def test_repr(self):
-        assert repr(self.case_insensitive_dict) == "{'Accept': 'application/json'}"
+        assert repr(
+            self.case_insensitive_dict
+        ) == "{'Accept': 'application/json'}"
 
     def test_copy(self):
         copy = self.case_insensitive_dict.copy()
diff --git a/tests/test_testserver.py b/tests/test_testserver.py
index caf1f938..dffd3dec 100644
--- a/tests/test_testserver.py
+++ b/tests/test_testserver.py
@@ -60,7 +60,9 @@ class TestTestServer:
     def test_basic_waiting_server(self):
         """the server waits for the block_server event to be set before closing"""
         block_server = threading.Event()
-        with Server.basic_response_server(wait_to_close_event=block_server) as (
+        with Server.basic_response_server(
+            wait_to_close_event=block_server
+        ) as (
             host, port
         ):
             sock = socket.socket()
@@ -73,7 +75,9 @@ class TestTestServer:
     def test_multiple_requests(self):
         """multiple requests can be served"""
         requests_to_handle = 5
-        server = Server.basic_response_server(requests_to_handle=requests_to_handle)
+        server = Server.basic_response_server(
+            requests_to_handle=requests_to_handle
+        )
         with server as (host, port):
             server_url = 'http://{0}:{1}'.format(host, port)
             for _ in range(requests_to_handle):
@@ -83,7 +87,9 @@ class TestTestServer:
             with pytest.raises(requests.exceptions.ConnectionError):
                 r = requests.get(server_url)
 
-    @pytest.mark.skip(reason="this fails non-deterministically under pytest-xdist")
+    @pytest.mark.skip(
+        reason="this fails non-deterministically under pytest-xdist"
+    )
     def test_request_recovery(self):
         """can check the requests content"""
         # TODO: figure out why this sometimes fails when using pytest-xdist.
diff --git a/tests/test_utils.py b/tests/test_utils.py
index 7b42ca72..1bfd65a4 100644
--- a/tests/test_utils.py
+++ b/tests/test_utils.py
@@ -171,7 +171,8 @@ class TestGetEnvironProxies:
     @pytest.fixture(autouse=True, params=['no_proxy', 'NO_PROXY'])
     def no_proxy(self, request, monkeypatch):
         monkeypatch.setenv(
-            request.param, '192.168.0.0/24,127.0.0.1,localhost.localdomain,172.16.1.1'
+            request.param,
+            '192.168.0.0/24,127.0.0.1,localhost.localdomain,172.16.1.1',
         )
 
     @pytest.mark.parametrize(
@@ -189,14 +190,22 @@ class TestGetEnvironProxies:
 
     @pytest.mark.parametrize(
         'url',
-        ('http://192.168.1.1:5000/', 'http://192.168.1.1/', 'http://www.requests.com/'),
+        (
+            'http://192.168.1.1:5000/',
+            'http://192.168.1.1/',
+            'http://www.requests.com/',
+        ),
     )
     def test_not_bypass(self, url):
         assert get_environ_proxies(url, no_proxy=None) != {}
 
     @pytest.mark.parametrize(
         'url',
-        ('http://192.168.1.1:5000/', 'http://192.168.1.1/', 'http://www.requests.com/'),
+        (
+            'http://192.168.1.1:5000/',
+            'http://192.168.1.1/',
+            'http://www.requests.com/',
+        ),
     )
     def test_bypass_no_proxy_keyword(self, url):
         no_proxy = '192.168.1.1,requests.com'
@@ -260,7 +269,9 @@ class TestAddressInNetwork:
 
 class TestGuessFilename:
 
-    @pytest.mark.parametrize('value', (1, type('Fake', (object,), {'name': 1})()))
+    @pytest.mark.parametrize(
+        'value', (1, type('Fake', (object,), {'name': 1})())
+    )
     def test_guess_filename_invalid(self, value):
         assert guess_filename(value) is None
 
@@ -362,7 +373,10 @@ ENCODED_PASSWORD = basics.quote(PASSWORD, '')
             'http://user:pass%20pass@complex.url.com/path?query=yes',
             ('user', 'pass pass'),
         ),
-        ('http://user:pass pass@complex.url.com/path?query=yes', ('user', 'pass pass')),
+        (
+            'http://user:pass pass@complex.url.com/path?query=yes',
+            ('user', 'pass pass'),
+        ),
         (
             'http://user%25user:pass@complex.url.com/path?query=yes',
             ('user%user', 'pass'),
@@ -400,7 +414,8 @@ def test_unquote_unreserved(uri, expected):
 
 
 @pytest.mark.parametrize(
-    'mask, expected', ((8, '255.0.0.0'), (24, '255.255.255.0'), (25, '255.255.255.128'))
+    'mask, expected',
+    ((8, '255.0.0.0'), (24, '255.255.255.0'), (25, '255.255.255.128')),
 )
 def test_dotted_netmask(mask, expected):
     assert dotted_netmask(mask) == expected
@@ -432,7 +447,10 @@ def test_select_proxies(url, expected, proxies):
 @pytest.mark.parametrize(
     'value, expected',
     (
-        ('foo="is a fish", bar="as well"', {'foo': 'is a fish', 'bar': 'as well'}),
+        (
+            'foo="is a fish", bar="as well"',
+            {'foo': 'is a fish', 'bar': 'as well'},
+        ),
         ('key_without_value', {'key_without_value': None}),
     ),
 )
@@ -445,7 +463,9 @@ def test_parse_dict_header(value, expected):
     (
         (CaseInsensitiveDict(), None),
         (
-            CaseInsensitiveDict({'content-type': 'application/json; charset=utf-8'}),
+            CaseInsensitiveDict(
+                {'content-type': 'application/json; charset=utf-8'}
+            ),
             'utf-8',
         ),
         (CaseInsensitiveDict({'content-type': 'text/plain'}), 'ISO-8859-1'),
@@ -457,7 +477,14 @@ def test_get_encoding_from_headers(value, expected):
 
 @pytest.mark.parametrize(
     'value, length',
-    (('', 0), ('T', 1), ('Test', 4), ('Cont', 0), ('Other', -5), ('Content', None)),
+    (
+        ('', 0),
+        ('T', 1),
+        ('Test', 4),
+        ('Cont', 0),
+        ('Other', -5),
+        ('Content', None),
+    ),
 )
 def test_iter_slices(value, length):
     if length is None or (length <= 0 and len(value) > 0):
@@ -472,7 +499,13 @@ def test_iter_slices(value, length):
     (
         (
             '<http:/.../front.jpeg>; rel=front; type="image/jpeg"',
-            [{'url': 'http:/.../front.jpeg', 'rel': 'front', 'type': 'image/jpeg'}],
+            [
+                {
+                    'url': 'http:/.../front.jpeg',
+                    'rel': 'front',
+                    'type': 'image/jpeg',
+                }
+            ],
         ),
         ('<http:/.../front.jpeg>', [{'url': 'http:/.../front.jpeg'}]),
         ('<http:/.../front.jpeg>;', [{'url': 'http:/.../front.jpeg'}]),
@@ -501,7 +534,9 @@ def test_prepend_scheme_if_needed(value, expected):
     assert prepend_scheme_if_needed(value, 'http') == expected
 
 
-@pytest.mark.parametrize('value, expected', (('T', 'T'), (b'T', 'T'), (u'T', 'T')))
+@pytest.mark.parametrize(
+    'value, expected', (('T', 'T'), (b'T', 'T'), (u'T', 'T'))
+)
 def test_to_native_string(value, expected):
     assert to_native_string(value) == expected
 
@@ -509,7 +544,10 @@ def test_to_native_string(value, expected):
 @pytest.mark.parametrize(
     'url, expected',
     (
-        ('http://u:p@example.com/path?a=1#test', 'http://example.com/path?a=1'),
+        (
+            'http://u:p@example.com/path?a=1#test',
+            'http://example.com/path?a=1',
+        ),
         ('http://example.com/path', 'http://example.com/path'),
         ('//u:p@example.com/path', '//example.com/path'),
         ('//example.com/path', '//example.com/path'),
@@ -561,7 +599,8 @@ def test_add_dict_to_cookiejar(cookiejar):
 
 
 @pytest.mark.parametrize(
-    'value, expected', ((u'test', True), (u'æíöû', False), (u'ジェーピーニック', False))
+    'value, expected',
+    ((u'test', True), (u'æíöû', False), (u'ジェーピーニック', False)),
 )
 def test_unicode_is_ascii(value, expected):
     assert unicode_is_ascii(value) is expected
@@ -605,7 +644,9 @@ def test_should_bypass_proxies_no_proxy(url, expected, monkeypatch):
         ('http://192.168.0.1/', False, ''),
     ),
 )
-def test_should_bypass_proxies_win_registry(url, expected, override, monkeypatch):
+def test_should_bypass_proxies_win_registry(
+    url, expected, override, monkeypatch
+):
     """Tests for function should_bypass_proxies to check if proxy
     can be bypassed or not with Windows registry settings
     """
diff --git a/tests/testserver/server.py b/tests/testserver/server.py
index e8ff4ab6..c766b32a 100644
--- a/tests/testserver/server.py
+++ b/tests/testserver/server.py
@@ -46,7 +46,9 @@ class Server(threading.Thread):
     def text_response_server(cls, text, request_timeout=0.5, **kwargs):
 
         def text_response_handler(sock):
-            request_content = consume_socket_content(sock, timeout=request_timeout)
+            request_content = consume_socket_content(
+                sock, timeout=request_timeout
+            )
             sock.send(text.encode('utf-8'))
             return request_content