[Python-modules-team] My Pip installation is broken after upgrading Debian from oldstable/Wheezy to stable/Jessie...

[Ant Dude]

Dear Sir or Madam:

Hello.

A couple days ago, I upgraded my old Debian from oldstable/Wheezy to 
stable/Jessie but its Pip now crashes as shown below:

$ pip install
Traceback (most recent call last):
File "/usr/bin/pip", line 9, in
load_entry_point('pip==1.5.6', 'console_scripts', 'pip')()
File "/usr/lib/python2.7/dist-packages/pkg_resources.py", line 356, in 
load_entry_point
return get_distribution(dist).load_entry_point(group, name)
File "/usr/lib/python2.7/dist-packages/pkg_resources.py", line 2476, in 
load_entry_point
return ep.load()
File "/usr/lib/python2.7/dist-packages/pkg_resources.py", line 2190, in load
['name'])
File "/usr/lib/python2.7/dist-packages/pip/init.py", line 74, in
from pip.vcs import git, mercurial, subversion, bazaar # noqa
File "/usr/lib/python2.7/dist-packages/pip/vcs/mercurial.py", line 9, in
from pip.download import path_to_url
File "/usr/lib/python2.7/dist-packages/pip/download.py", line 25, in
from requests.compat import IncompleteRead
ImportError: cannot import name IncompleteRead

$ python
Python 2.7.9 (default, Mar 1 2015, 12:57:24)
[GCC 4.9.2] on linux2
Type "help", "copyright", "credits" or "license" for more information.
             exit
             Use exit() or Ctrl-D (i.e. EOF) to exit

How do I fix this? I already tried apt-get purge and reinstalling 
python-pip, python-colorama, python-distlib, python-html5lib, 
python-ndg-httpsclient, python-requests, python-urllib3, and 
python-wheel packages. Pip worked before the upgrade. :(

Thank you in advance. :)

Sincerely yours,
Ant Dude