title: IronPython 2.7.8 with pip
body: <p>After installed IronPython 2.7.8 (latest stable build) on Windows 10, I tried run pip but I got error like this:</p>
  
  <pre><code>PS C:\Program Files\IronPython 2.7&gt; ipy.exe -m pip install numpy
  Unhandled exception:
  Traceback (most recent call last):
    File "C:\Program Files\IronPython 2.7\Lib\runpy.py", line 187, in run_module
    File "C:\Program Files\IronPython 2.7\Lib\site-packages\pip\_vendor\pyparsing.py", line 1261, in setParseAction
    File "C:\Program Files\IronPython 2.7\Lib\site-packages\pip\_vendor\pyparsing.py", line 1043, in _trim_arity
    File "C:\Program Files\IronPython 2.7\Lib\runpy.py", line 81, in _run_module_code
    File "C:\Program Files\IronPython 2.7\Lib\runpy.py", line 72, in _run_code
    File "C:\Program Files\IronPython 2.7\Lib\site-packages\pip\__main__.py", line 16, in &lt;module&gt;
    File "C:\Program Files\IronPython 2.7\Lib\site-packages\pip\_internal\__init__.py", line 42, in &lt;module&gt;
    File "C:\Program Files\IronPython 2.7\Lib\site-packages\pip\_internal\cmdoptions.py", line 16, in &lt;module&gt;
    File "C:\Program Files\IronPython 2.7\Lib\site-packages\pip\_internal\index.py", line 25, in &lt;module&gt;
    File "C:\Program Files\IronPython 2.7\Lib\site-packages\pip\_internal\download.py", line 40, in &lt;module&gt;
    File "C:\Program Files\IronPython 2.7\Lib\site-packages\pip\_internal\utils\logging.py", line 9, in &lt;module&gt;
    File "C:\Program Files\IronPython 2.7\Lib\site-packages\pip\_internal\utils\misc.py", line 21, in &lt;module&gt;
    File "C:\Program Files\IronPython 2.7\Lib\site-packages\pip\_vendor\pkg_resources\__init__.py", line 77, in &lt;module&gt;
    File "C:\Program Files\IronPython 2.7\Lib\site-packages\pip\_vendor\packaging\requirements.py", line 9, in &lt;module&gt;
    File "C:\Program Files\IronPython 2.7\Lib\site-packages\pip\_vendor\pyparsing.py", line 4734, in &lt;module&gt;
  IndexError: index out of range: -1
  PS C:\Program Files\IronPython 2.7&gt;
  </code></pre>
  
  <p>I have no clue to solve this error. It seems to be problem of IronPython? I have no way to install packages to the IronPython hence, cannot do any development with that. Anyone can help?</p>