title: pip install traceback error while installing packages in Python
body: <p>I'm having issues to install python packages using 'pip', i have no problems until a couple of days ago, but now suddenly I have the error below every time i want to install something.
  I'm using Python 2.7 on windows, and I already reinstall 'pip' by still the same.</p>
  
  <pre><code>Traceback (most recent call last):   
     File "C:\Python27\Scripts\pip-script.py", line 9, in &lt;module&gt;
     load_entry_point('pip==1.5.6', 'console_scripts', 'pip')()
  
    File "build\bdist.win32\egg\pkg_resources.py", line 339, in load_entry_point
      ns.clear()
  
    File "build\bdist.win32\egg\pkg_resources.py", line 2470, in load_entry_point
      else:
  
    File "build\bdist.win32\egg\pkg_resources.py", line 2184, in load
      raise ValueError
  
    File "C:\Python27\lib\site-packages\pip\__init__.py", line 11, in &lt;module&gt;
      from pip.vcs import git, mercurial, subversion, bazaar  # noqa
  
    File "C:\Python27\lib\site-packages\pip\vcs\mercurial.py", line 9, in &lt;module&gt;
      from pip.download import path_to_url
  
    File "C:\Python27\lib\site-packages\pip\download.py", line 26, in &lt;module&gt;
      from requests.compat import IncompleteRead
  </code></pre>
  
  <p>ImportError: <strong>cannot import name IncompleteRead</strong></p>