Remove requests.packages for v3.0.0

As v3.0.0 already includes other backwards incompatible changes, it is a
good time to remove the old entry point for vendored packages. Cleans up
compatibility shims.

requests/__init__.py

@@ -110,7 +110,6 @@ from .__version__ import __build__, __author__, __author_email__, __license__
 from .__version__ import __copyright__, __cake__
 
 from . import utils
-from . import packages
 from .models import Request, Response, PreparedRequest
 from .api import request, get, head, post, patch, put, delete, options
 from .sessions import session, Session

requests/packages.py

@@ -1,14 +0,0 @@
-import sys
-
-# This code exists for backwards compatibility reasons.
-# I don't like it either. Just look the other way. :)
-
-for package in ('urllib3', 'idna', 'chardet'):
-    locals()[package] = __import__(package)
-    # This traversal is apparently necessary such that the identities are
-    # preserved (requests.packages.urllib3.* is urllib3.*)
-    for mod in list(sys.modules):
-        if mod == package or mod.startswith(package + '.'):
-            sys.modules['requests.packages.' + mod] = sys.modules[mod]
-
-# Kinda cool, though, right?

tests/test_packages.py

@@ -1,13 +0,0 @@
-import requests
-
-
-def test_can_access_urllib3_attribute():
-    requests.packages.urllib3
-
-
-def test_can_access_idna_attribute():
-    requests.packages.idna
-
-
-def test_can_access_chardet_attribute():
-    requests.packages.chardet

tests/test_requests.py

@@ -82,8 +82,6 @@ class TestRequests:
         requests.put
         requests.patch
         requests.post
-        # Not really an entry point, but people rely on it.
-        from requests.packages.urllib3.poolmanager import PoolManager
 
     @pytest.mark.parametrize(
         'exception, url', (