diff --git a/requests3/__init__.py b/requests3/__init__.py
index 0ad0a281..55da8abd 100644
--- a/requests3/__init__.py
+++ b/requests3/__init__.py
@@ -114,10 +114,9 @@ from .__version__ import __build__, __author__, __author_email__, __license__
 from .__version__ import __copyright__, __cake__
 
 from . import utils
-from .models import Request, Response, PreparedRequest
-from .api import request, get, head, post, patch, put, delete, options
-from .sessions import Session, AsyncSession
-from .status_codes import codes
+from .http_models import Request, Response, PreparedRequest
+from .http_sessions import Session, AsyncSession
+from .http_stati import codes
 from .exceptions import (
     RequestException,
     Timeout,
@@ -137,3 +136,92 @@ from logging import NullHandler
 logging.getLogger(__name__).addHandler(NullHandler())
 # FileModeWarnings go off per the default.
 warnings.simplefilter("default", FileModeWarning, append=True)
+
+
+
+# -*- coding: utf-8 -*-
+"""
+requests.api
+~~~~~~~~~~~~
+
+This module implements the Requests API.
+
+:copyright: (c) 2012 by Kenneth Reitz.
+:license: Apache2, see LICENSE for more details.
+"""
+
+from . import http_sessions as sessions
+from . import _types as types
+
+
+def request(
+    method: types.Method, url: types.URL, *, session: types.Session = None, **kwargs
+) -> types.Response:
+    """Constructs and sends a :class:`Request <Request>`.
+
+    :param method: method for the new :class:`Request` object.
+    :param url: URL for the new :class:`Request` object.
+    :param session: :class:`Session` object to use for this request. If none is given, one will be provided.
+    :param params: (optional) Dictionary or bytes to be sent in the query string for the :class:`Request`.
+    :param data: (optional) Dictionary or list of tuples ``[(key, value)]`` (will be form-encoded), bytes, or file-like object to send in the body of the :class:`Request`.
+    :param json: (optional) json data to send in the body of the :class:`Request`.
+    :param headers: (optional) Dictionary of HTTP Headers to send with the :class:`Request`.
+    :param cookies: (optional) Dict or CookieJar object to send with the :class:`Request`.
+    :param files: (optional) Dictionary of ``'name': file-like-objects`` (or ``{'name': file-tuple}``) for multipart encoding upload.
+        ``file-tuple`` can be a 2-tuple ``('filename', fileobj)``, 3-tuple ``('filename', fileobj, 'content_type')``
+        or a 4-tuple ``('filename', fileobj, 'content_type', custom_headers)``, where ``'content-type'`` is a string
+        defining the content type of the given file and ``custom_headers`` a dict-like object containing additional headers
+        to add for the file.
+    :param auth: (optional) Auth tuple to enable Basic/Digest/Custom HTTP Auth.
+    :param timeout: (optional) How many seconds to wait for the server to send data
+        before giving up, as a float, or a :ref:`(connect timeout, read
+        timeout) <timeouts>` tuple.
+    :type timeout: float or tuple
+    :param allow_redirects: (optional) Boolean. Enable/disable GET/OPTIONS/POST/PUT/PATCH/DELETE/HEAD redirection. Defaults to ``True``.
+    :type allow_redirects: bool
+    :param proxies: (optional) Dictionary mapping protocol to the URL of the proxy.
+    :param verify: (optional) Either a boolean, in which case it controls whether we verify
+            the server's TLS certificate, or a string, in which case it must be a path
+            to a CA bundle to use. Defaults to ``True``.
+    :param stream: (optional) if ``False``, the response content will be immediately downloaded.
+    :param cert: (optional) if String, path to ssl client cert file (.pem). If Tuple, ('cert', 'key') pair.
+    :return: :class:`Response <Response>` object
+    :rtype: requests.Response
+
+    Usage::
+
+      >>> import requests
+      >>> req = requests.request('GET', 'https://httpbin.org/get')
+      <Response [200]>
+    """
+    # By using the 'with' statement we are sure the session is closed, thus we
+    # avoid leaving sockets open which can trigger a ResourceWarning in some
+    # cases, and look like a memory leak in others.
+    session = sessions.Session() if session is None else session
+    with session:
+        return session.request(method=method, url=url, **kwargs)
+
+
+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.
+    :param params: (optional) Dictionary, list of tuples or bytes to send
+        in the query string for the :class:`Request`.
+    :param \*\*kwargs: Optional arguments that ``request`` takes.
+    :return: :class:`Response <Response>` object
+    :rtype: requests.Response
+    """
+    kwargs.setdefault("allow_redirects", True)
+    return request("get", url, params=params, **kwargs)
+
+def head(url: types.URL, **kwargs) -> types.Response:
+    r"""Sends a HEAD request.
+
+    :param url: URL for the new :class:`Request` object.
+    :param \*\*kwargs: Optional arguments that ``request`` takes.
+    :return: :class:`Response <Response>` object
+    :rtype: requests.Response
+    """
+    kwargs.setdefault("allow_redirects", False)
+    return request("head", url, **kwargs)
diff --git a/requests3/basics.py b/requests3/_basics.py
similarity index 100%
rename from requests3/basics.py
rename to requests3/_basics.py
diff --git a/requests3/hooks.py b/requests3/_hooks.py
similarity index 100%
rename from requests3/hooks.py
rename to requests3/_hooks.py
diff --git a/requests3/_internal_utils.py b/requests3/_internal_utils.py
index a15e1116..37bc7173 100644
--- a/requests3/_internal_utils.py
+++ b/requests3/_internal_utils.py
@@ -7,7 +7,7 @@ Provides utility functions that are consumed internally by Requests
 which depend on extremely few external helpers (such as compat)
 """
 
-from .basics import builtin_str, str
+from ._basics import builtin_str, str
 
 
 def to_native_string(string, encoding='ascii'):
diff --git a/requests3/structures.py b/requests3/_structures.py
similarity index 99%
rename from requests3/structures.py
rename to requests3/_structures.py
index c88d744d..63da49e2 100644
--- a/requests3/structures.py
+++ b/requests3/_structures.py
@@ -8,7 +8,7 @@ Data structures that power Requests.
 
 import collections
 
-from .basics import basestring, OrderedDict
+from ._basics import basestring, OrderedDict
 
 
 class CaseInsensitiveDict(collections.MutableMapping):
diff --git a/requests3/_structures.py.ca21d3379eb0bd9467ef35e763c5290c.py b/requests3/_structures.py.ca21d3379eb0bd9467ef35e763c5290c.py
new file mode 100644
index 00000000..63da49e2
--- /dev/null
+++ b/requests3/_structures.py.ca21d3379eb0bd9467ef35e763c5290c.py
@@ -0,0 +1,229 @@
+# -*- coding: utf-8 -*-
+"""
+requests.structures
+~~~~~~~~~~~~~~~~~~~
+
+Data structures that power Requests.
+"""
+
+import collections
+
+from ._basics import basestring, OrderedDict
+
+
+class CaseInsensitiveDict(collections.MutableMapping):
+    """A case-insensitive ``dict``-like object.
+
+    Implements all methods and operations of
+    ``collections.MutableMapping`` as well as dict's ``copy``. Also
+    provides ``lower_items``.
+
+    All keys are expected to be strings. The structure remembers the
+    case of the last key to be set, and ``iter(instance)``,
+    ``keys()``, ``items()``, ``iterkeys()``, and ``iteritems()``
+    will contain case-sensitive keys. However, querying and contains
+    testing is case insensitive::
+
+        cid = CaseInsensitiveDict()
+        cid['Accept'] = 'application/json'
+        cid['aCCEPT'] == 'application/json'  # True
+        list(cid) == ['Accept']  # True
+
+    For example, ``headers['content-encoding']`` will return the
+    value of a ``'Content-Encoding'`` response header, regardless
+    of how the header name was originally stored.
+
+    If the constructor, ``.update``, or equality comparison
+    operations are given keys that have equal ``.lower()``s, the
+    behavior is undefined.
+    """
+    __slots__ = ('_store')
+
+    def __init__(self, data=None, **kwargs):
+        self._store = collections.OrderedDict()
+        if data is None:
+            data = {}
+        self.update(data, **kwargs)
+
+    def __setitem__(self, key, value):
+        # Use the lowercased key for lookups, but store the actual
+        # key alongside the value.
+        self._store[key.lower()] = (key, value)
+
+    def __getitem__(self, key):
+        return self._store[key.lower()][1]
+
+    def __delitem__(self, key):
+        del self._store[key.lower()]
+
+    def __iter__(self):
+        return (casedkey for casedkey, mappedvalue in self._store.values())
+
+    def __len__(self):
+        return len(self._store)
+
+    def lower_items(self):
+        """Like iteritems(), but with all lowercase keys."""
+        return (
+            (lowerkey, keyval[1]) for (lowerkey, keyval) in self._store.items()
+        )
+
+    def __eq__(self, other):
+        if isinstance(other, collections.Mapping):
+            other = CaseInsensitiveDict(other)
+        else:
+            return NotImplemented
+
+        # Compare insensitively
+        return dict(self.lower_items()) == dict(other.lower_items())
+
+
+    # Copy is required
+    def copy(self):
+        return CaseInsensitiveDict(self._store.values())
+
+    def __repr__(self):
+        return str(dict(self.items()))
+
+
+class HTTPHeaderDict(CaseInsensitiveDict):
+    """A case-insensitive ``dict``-like object suitable for HTTP headers that
+    supports multiple values with the same key, via the ``add``, ``extend``,
+    ``multiget`` and ``multiset`` methods.
+    """
+
+    def __init__(self, data=None, **kwargs):
+        super(HTTPHeaderDict, self).__init__()
+        self.extend({} if data is None else data, **kwargs)
+
+
+    # We'll store tuples in the internal dictionary, but present them as a
+    # concatenated string when we use item access methods.
+    #
+    def __setitem__(self, key, val):
+        # Special–case null values.
+        if (not isinstance(val, basestring)) and (val is not None):
+            raise ValueError('only string-type values (or None) are allowed')
+
+        super(HTTPHeaderDict, self).__setitem__(key, (val,))
+
+    def __getitem__(self, key):
+        val = super(HTTPHeaderDict, self).__getitem__(key)
+        # Special–case null values.
+        if len(val) == 1 and val[0] is None:
+            return val[0]
+
+        return ', '.join(val)
+
+    def lower_items(self):
+        return (
+            (lk, ', '.join(vals)) for (lk, (k, vals)) in self._store.items()
+        )
+
+    def copy(self):
+        return type(self)(self)
+
+    def getlist(self, key):
+        """Returns a list of all the values for the named field. Returns an
+        empty list if the key isn't present in the dictionary."""
+        return list(self._store.get(key.lower(), (None, []))[1])
+
+    def setlist(self, key, values):
+        """Set a sequence of strings to the associated key - this will overwrite
+        any previously stored value."""
+        if not isinstance(values, (list, tuple)):
+            raise ValueError('argument is not sequence')
+
+        if any(not isinstance(v, basestring) for v in values):
+            raise ValueError('non-string items in sequence')
+
+        if not values:
+            self.pop(key, None)
+            return
+
+        super(HTTPHeaderDict, self).__setitem__(key, tuple(values))
+
+    def _extend(self, key, values):
+        new_value_tpl = key, values
+        # Inspired by urllib3's implementation - use one call which should be
+        # suitable for the common case.
+        old_value_tpl = self._store.setdefault(key.lower(), new_value_tpl)
+        if old_value_tpl is not new_value_tpl:
+            old_key, old_values = old_value_tpl
+            self._store[key.lower()] = (old_key, old_values + values)
+
+    def add(self, key, val):
+        """Adds a key, value pair to this dictionary - if there is already a
+        value for this key, then the value will be appended to those values.
+        """
+        if not isinstance(val, basestring):
+            raise ValueError('value must be a string-type object')
+
+        self._extend(key, (val,))
+
+    def extend(self, *args, **kwargs):
+        """Like update, but will add values to existing sequences rather than
+        replacing them. You can pass a mapping object or a sequence of two
+        tuples - values in these objects can be strings or sequence of strings.
+        """
+        if len(args) > 1:
+            raise TypeError(
+                f"extend() takes at most 1 positional "
+                "arguments ({len(args)} given)"
+            )
+
+        for other in args + (kwargs,):
+            if isinstance(other, collections.Mapping):
+                # See if looks like a HTTPHeaderDict (either urllib3's
+                # implementation or ours). If so, then we have to add values
+                # in one go for each key.
+                multiget = getattr(other, 'getlist', None)
+                if multiget:
+                    for key in other:
+                        self._extend(key, tuple(multiget(key)))
+                    continue
+
+                # Otherwise, just walk over items to get them.
+                item_seq = other.items()
+            else:
+                item_seq = other
+            for ik, iv in item_seq:
+                if isinstance(iv, basestring):
+                    self._extend(ik, (iv,))
+                elif any(not isinstance(v, basestring) for v in iv):
+                    raise ValueError('non-string items in sequence')
+
+                else:
+                    self._extend(ik, tuple(iv))
+
+    @property
+    def _as_dict(self):
+        """A dictionary representation of the HTTPHeaderDict."""
+        d = {}
+        for k, vals in self._store.values():
+            d[k] = vals[0] if len(vals) == 1 else vals
+        return d
+
+    def __repr__(self):
+        return repr(self._as_dict)
+
+
+class LookupDict(dict):
+    """Dictionary lookup object."""
+
+    def __init__(self, name=None):
+        self.name = name
+        super(LookupDict, self).__init__()
+
+    def __repr__(self):
+        return f'<lookup \'{self.name}\'>'
+
+    def __getitem__(self, key):
+        # We allow fall-through here, so values default to None
+        return self.__dict__.get(key, None)
+
+    def __iter__(self):
+        return super(LookupDict, self).__dir__()
+
+    def get(self, key, default=None):
+        return self.__dict__.get(key, default)
diff --git a/requests3/types.py b/requests3/_types.py
similarity index 91%
rename from requests3/types.py
rename to requests3/_types.py
index 4b609867..c9f0dff1 100644
--- a/requests3/types.py
+++ b/requests3/_types.py
@@ -14,10 +14,10 @@ from typing import (
     Dict,
 )
 
-from .import auth
-from .models import Response, PreparedRequest
-from .cookies import RequestsCookieJar
-from .sessions import Session
+from .import http_auth as auth
+from .http_models import Response, PreparedRequest
+from .http_cookies import RequestsCookieJar
+from .http_sessions import Session
 
 _ParamsMappingValueType = Union[
     str, bytes, int, float, Iterable[Union[str, bytes, int, float]]
diff --git a/requests3/api.py b/requests3/api.py
deleted file mode 100644
index b6265ba5..00000000
--- a/requests3/api.py
+++ /dev/null
@@ -1,154 +0,0 @@
-# -*- coding: utf-8 -*-
-"""
-requests.api
-~~~~~~~~~~~~
-
-This module implements the Requests API.
-
-:copyright: (c) 2012 by Kenneth Reitz.
-:license: Apache2, see LICENSE for more details.
-"""
-
-from . import sessions
-from . import types
-
-
-def request(
-    method: types.Method, url: types.URL, *, session: types.Session = None, **kwargs
-) -> types.Response:
-    """Constructs and sends a :class:`Request <Request>`.
-
-    :param method: method for the new :class:`Request` object.
-    :param url: URL for the new :class:`Request` object.
-    :param session: :class:`Session` object to use for this request. If none is given, one will be provided.
-    :param params: (optional) Dictionary or bytes to be sent in the query string for the :class:`Request`.
-    :param data: (optional) Dictionary or list of tuples ``[(key, value)]`` (will be form-encoded), bytes, or file-like object to send in the body of the :class:`Request`.
-    :param json: (optional) json data to send in the body of the :class:`Request`.
-    :param headers: (optional) Dictionary of HTTP Headers to send with the :class:`Request`.
-    :param cookies: (optional) Dict or CookieJar object to send with the :class:`Request`.
-    :param files: (optional) Dictionary of ``'name': file-like-objects`` (or ``{'name': file-tuple}``) for multipart encoding upload.
-        ``file-tuple`` can be a 2-tuple ``('filename', fileobj)``, 3-tuple ``('filename', fileobj, 'content_type')``
-        or a 4-tuple ``('filename', fileobj, 'content_type', custom_headers)``, where ``'content-type'`` is a string
-        defining the content type of the given file and ``custom_headers`` a dict-like object containing additional headers
-        to add for the file.
-    :param auth: (optional) Auth tuple to enable Basic/Digest/Custom HTTP Auth.
-    :param timeout: (optional) How many seconds to wait for the server to send data
-        before giving up, as a float, or a :ref:`(connect timeout, read
-        timeout) <timeouts>` tuple.
-    :type timeout: float or tuple
-    :param allow_redirects: (optional) Boolean. Enable/disable GET/OPTIONS/POST/PUT/PATCH/DELETE/HEAD redirection. Defaults to ``True``.
-    :type allow_redirects: bool
-    :param proxies: (optional) Dictionary mapping protocol to the URL of the proxy.
-    :param verify: (optional) Either a boolean, in which case it controls whether we verify
-            the server's TLS certificate, or a string, in which case it must be a path
-            to a CA bundle to use. Defaults to ``True``.
-    :param stream: (optional) if ``False``, the response content will be immediately downloaded.
-    :param cert: (optional) if String, path to ssl client cert file (.pem). If Tuple, ('cert', 'key') pair.
-    :return: :class:`Response <Response>` object
-    :rtype: requests.Response
-
-    Usage::
-
-      >>> import requests
-      >>> req = requests.request('GET', 'https://httpbin.org/get')
-      <Response [200]>
-    """
-    # By using the 'with' statement we are sure the session is closed, thus we
-    # avoid leaving sockets open which can trigger a ResourceWarning in some
-    # cases, and look like a memory leak in others.
-    session = sessions.Session() if session is None else session
-    with session:
-        return session.request(method=method, url=url, **kwargs)
-
-
-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.
-    :param params: (optional) Dictionary, list of tuples or bytes to send
-        in the query string for the :class:`Request`.
-    :param \*\*kwargs: Optional arguments that ``request`` takes.
-    :return: :class:`Response <Response>` object
-    :rtype: requests.Response
-    """
-    kwargs.setdefault("allow_redirects", True)
-    return request("get", url, params=params, **kwargs)
-
-
-def options(url: types.URL, **kwargs) -> types.Response:
-    r"""Sends an OPTIONS request.
-
-    :param url: URL for the new :class:`Request` object.
-    :param \*\*kwargs: Optional arguments that ``request`` takes.
-    :return: :class:`Response <Response>` object
-    :rtype: requests.Response
-    """
-    kwargs.setdefault("allow_redirects", True)
-    return request("options", url, **kwargs)
-
-
-def head(url: types.URL, **kwargs) -> types.Response:
-    r"""Sends a HEAD request.
-
-    :param url: URL for the new :class:`Request` object.
-    :param \*\*kwargs: Optional arguments that ``request`` takes.
-    :return: :class:`Response <Response>` object
-    :rtype: requests.Response
-    """
-    kwargs.setdefault("allow_redirects", False)
-    return request("head", url, **kwargs)
-
-
-def post(
-    url: types.URL, *, data: types.Data = None, json: types.JSON = None, **kwargs
-) -> types.Response:
-    r"""Sends a POST request.
-
-    :param url: URL for the new :class:`Request` object.
-    :param data: (optional) Dictionary, list of tuples, bytes, or file-like
-        object to send in the body of the :class:`Request`.
-    :param json: (optional) json data to send in the body of the :class:`Request`.
-    :param \*\*kwargs: Optional arguments that ``request`` takes.
-    :return: :class:`Response <Response>` object
-    :rtype: requests.Response
-    """
-    return request("post", url, data=data, json=json, **kwargs)
-
-
-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.
-    :param data: (optional) Dictionary, list of tuples, bytes, or file-like
-        object to send in the body of the :class:`Request`.
-    :param json: (optional) json data to send in the body of the :class:`Request`.
-    :param \*\*kwargs: Optional arguments that ``request`` takes.
-    :return: :class:`Response <Response>` object
-    :rtype: requests.Response
-    """
-    return request("put", url, data=data, **kwargs)
-
-
-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.
-    :param data: (optional) Dictionary, list of tuples, bytes, or file-like
-        object to send in the body of the :class:`Request`.
-    :param json: (optional) json data to send in the body of the :class:`Request`.
-    :param \*\*kwargs: Optional arguments that ``request`` takes.
-    :return: :class:`Response <Response>` object
-    :rtype: requests.Response
-    """
-    return request("patch", url, data=data, **kwargs)
-
-
-def delete(url: types.URL, **kwargs) -> types.Response:
-    r"""Sends a DELETE request.
-
-    :param url: URL for the new :class:`Request` object.
-    :param \*\*kwargs: Optional arguments that ``request`` takes.
-    :return: :class:`Response <Response>` object
-    :rtype: requests.Response
-    """
-    return request("delete", url, **kwargs)
diff --git a/requests3/certs.py b/requests3/certs.py
deleted file mode 100644
index c811c194..00000000
--- a/requests3/certs.py
+++ /dev/null
@@ -1,17 +0,0 @@
-#!/usr/bin/env python
-# -*- coding: utf-8 -*-
-"""
-requests.certs
-~~~~~~~~~~~~~~
-
-This module returns the preferred default CA certificate bundle. There is
-only one — the one from the certifi package.
-
-If you are packaging Requests, e.g., for a Linux distribution or a managed
-environment, you can change the definition of where() to return a separately
-packaged CA bundle.
-"""
-from certifi import where
-
-if __name__ == '__main__':
-    print(where())
diff --git a/requests3/adapters.py b/requests3/http_adapters.py
similarity index 99%
rename from requests3/adapters.py
rename to requests3/http_adapters.py
index ad183474..a0ab6002 100644
--- a/requests3/adapters.py
+++ b/requests3/http_adapters.py
@@ -28,8 +28,8 @@ from .core._http.exceptions import ReadTimeoutError
 from .core._http.exceptions import SSLError as _SSLError
 from .core._http.exceptions import ResponseError
 
-from .models import Response, AsyncResponse
-from .basics import urlparse, basestring
+from .http_models import Response, AsyncResponse
+from ._basics import urlparse, basestring
 from .utils import (
     DEFAULT_CA_BUNDLE_PATH,
     get_encoding_from_headers,
@@ -38,8 +38,8 @@ from .utils import (
     urldefragauth,
     select_proxy,
 )
-from .structures import HTTPHeaderDict
-from .cookies import extract_cookies_to_jar
+from ._structures import HTTPHeaderDict
+from .http_cookies import extract_cookies_to_jar
 from .exceptions import (
     ConnectionError,
     ConnectTimeout,
@@ -49,7 +49,7 @@ from .exceptions import (
     RetryError,
     InvalidScheme,
 )
-from .auth import _basic_auth_str
+from .http_auth import _basic_auth_str
 
 try:
     from .core._http.contrib.socks import SOCKSProxyManager
diff --git a/requests3/auth.py b/requests3/http_auth.py
similarity index 99%
rename from requests3/auth.py
rename to requests3/http_auth.py
index afe0bd4f..228e0dbd 100644
--- a/requests3/auth.py
+++ b/requests3/http_auth.py
@@ -14,8 +14,8 @@ import threading
 
 from base64 import b64encode
 
-from .basics import urlparse, str, basestring
-from .cookies import extract_cookies_to_jar
+from ._basics import urlparse, str, basestring
+from .http_cookies import extract_cookies_to_jar
 from ._internal_utils import to_native_string
 from .utils import parse_dict_header
 
diff --git a/requests3/cookies.py b/requests3/http_cookies.py
similarity index 99%
rename from requests3/cookies.py
rename to requests3/http_cookies.py
index e0716ab0..140a99c1 100644
--- a/requests3/cookies.py
+++ b/requests3/http_cookies.py
@@ -14,7 +14,7 @@ import calendar
 from collections.abc import MutableMapping
 
 from ._internal_utils import to_native_string
-from .basics import cookielib, urlparse, urlunparse, Morsel
+from ._basics import cookielib, urlparse, urlunparse, Morsel
 
 try:
     import threading
diff --git a/requests3/models.py b/requests3/http_models.py
similarity index 99%
rename from requests3/models.py
rename to requests3/http_models.py
index 968104bf..975f585d 100644
--- a/requests3/models.py
+++ b/requests3/http_models.py
@@ -24,12 +24,12 @@ from .core._http.exceptions import (
 )
 
 from io import UnsupportedOperation
-from .hooks import default_hooks
-from .structures import CaseInsensitiveDict
+from ._hooks import default_hooks
+from ._structures import CaseInsensitiveDict
 
 import requests3 as requests
-from .auth import HTTPBasicAuth
-from .cookies import cookiejar_from_dict, get_cookie_header, _copy_cookie_jar
+from .http_auth import HTTPBasicAuth
+from .http_cookies import cookiejar_from_dict, get_cookie_header, _copy_cookie_jar
 from .exceptions import (
     HTTPError,
     MissingScheme,
@@ -56,7 +56,7 @@ from .utils import (
     check_header_validity,
     is_stream,
 )
-from .basics import (
+from ._basics import (
     cookielib,
     urlunparse,
     urlsplit,
@@ -68,7 +68,7 @@ from .basics import (
     basestring,
 )
 import json as complexjson
-from .status_codes import codes
+from .http_stati import codes
 
 # : The set of HTTP status codes that indicate an automatically
 #: processable redirect.
diff --git a/requests3/sessions.py b/requests3/http_sessions.py
similarity index 98%
rename from requests3/sessions.py
rename to requests3/http_sessions.py
index 3c6168b1..5f8b3762 100644
--- a/requests3/sessions.py
+++ b/requests3/http_sessions.py
@@ -1,7 +1,7 @@
 # -*- coding: utf-8 -*-
 """
-requests.session
-~~~~~~~~~~~~~~~~
+requests.http_session
+~~~~~~~~~~~~~~~~~~~~~
 
 This module provides a Session object to manage and persist settings across
 requests (cookies, auth, proxies).
@@ -14,17 +14,17 @@ from datetime import timedelta
 
 from .core._http._backends.trio_backend import TrioBackend
 
-from .auth import _basic_auth_str
-from .basics import cookielib, urljoin, urlparse, str
-from .cookies import (
+from .http_auth import _basic_auth_str
+from ._basics import cookielib, urljoin, urlparse, str
+from .http_cookies import (
     cookiejar_from_dict,
     extract_cookies_to_jar,
     RequestsCookieJar,
     merge_cookies,
     _copy_cookie_jar,
 )
-from .models import Request, PreparedRequest, DEFAULT_REDIRECT_LIMIT
-from .hooks import default_hooks, dispatch_hook
+from .http_models import Request, PreparedRequest, DEFAULT_REDIRECT_LIMIT
+from ._hooks import default_hooks, dispatch_hook
 from ._internal_utils import to_native_string
 from .utils import to_key_val_list, default_headers, DEFAULT_PORTS
 from .exceptions import (
@@ -36,8 +36,8 @@ from .exceptions import (
     InvalidHeader,
 )
 
-from .structures import CaseInsensitiveDict
-from .adapters import HTTPAdapter, AsyncHTTPAdapter
+from ._structures import CaseInsensitiveDict
+from .http_adapters import HTTPAdapter, AsyncHTTPAdapter
 
 from .utils import (
     requote_uri,
@@ -49,10 +49,10 @@ from .utils import (
     rewind_body,
 )
 
-from .status_codes import codes
+from .http_stati import codes
 
 # formerly defined here, reexposed here for backward compatibility
-from .models import REDIRECT_STATI
+from .http_models import REDIRECT_STATI
 
 # Preferred clock, based on which one is more accurate on a given system.
 if sys.platform == "win32":
diff --git a/requests3/status_codes.py b/requests3/http_stati.py
similarity index 98%
rename from requests3/status_codes.py
rename to requests3/http_stati.py
index 433ab081..56ebd215 100644
--- a/requests3/status_codes.py
+++ b/requests3/http_stati.py
@@ -1,5 +1,5 @@
 # -*- coding: utf-8 -*-
-from .structures import LookupDict
+from ._structures import LookupDict
 
 _codes = {
     # Informational.
diff --git a/requests3/utils.py b/requests3/utils.py
index 0273625e..f358fb6b 100644
--- a/requests3/utils.py
+++ b/requests3/utils.py
@@ -23,11 +23,12 @@ import platform
 import zipfile
 from typing import Mapping
 
-from .__version__ import __version__
-from . import certs
+import certifi
 
-from .basics import parse_http_list as _parse_list_header
-from .basics import (
+from .__version__ import __version__
+
+from ._basics import parse_http_list as _parse_list_header
+from ._basics import (
     quote,
     urlparse,
     bytes,
@@ -41,9 +42,9 @@ from .basics import (
     proxy_bypass_environment,
     getproxies_environment
 )
-from .cookies import cookiejar_from_dict
-from .structures import HTTPHeaderDict
-from .cookies import RequestsCookieJar
+from .http_cookies import cookiejar_from_dict, RequestsCookieJar
+from ._structures import HTTPHeaderDict
+
 from .exceptions import (
     InvalidURL,
     InvalidHeader,
@@ -52,7 +53,7 @@ from .exceptions import (
 )
 
 NETRC_FILES = (".netrc", "_netrc")
-DEFAULT_CA_BUNDLE_PATH = certs.where()
+DEFAULT_CA_BUNDLE_PATH = certifi.where()
 DEFAULT_PORTS = (80, 443)
 if platform.system() == "Windows":
 
diff --git a/setup.py b/setup.py
index ced16693..1e5bcd9f 100644
--- a/setup.py
+++ b/setup.py
@@ -73,7 +73,8 @@ requires = [
     'chardet>=3.0.2,<3.1.0',
     'idna>=2.5,<2.9',
     'urllib3>=1.21.1,<1.25',
-    'certifi>=2017.4.17'
+    'certifi>=2017.4.17',
+    'requests-toolbelt'
 
 ]
 test_requirements = [