I get this:

Traceback (most recent call last):
  File "c:\Python27\lib\site-packages\virtualenv\_wheels\pip-7.0.1-py2.py3-none-any.whl\pip\basecommand.py", line 223, in main
    status = self.run(options, args)
  File "c:\Python27\lib\site-packages\virtualenv\_wheels\pip-7.0.1-py2.py3-none-any.whl\pip\commands\install.py", line 297, in run
    root=options.root_path,
  File "c:\Python27\lib\site-packages\virtualenv\_wheels\pip-7.0.1-py2.py3-none-any.whl\pip\req\req_set.py", line 622, in install
    **kwargs
  File "c:\Python27\lib\site-packages\virtualenv\_wheels\pip-7.0.1-py2.py3-none-any.whl\pip\req\req_install.py", line 808, in install
    self.move_wheel_files(self.source_dir, root=root)
  File "c:\Python27\lib\site-packages\virtualenv\_wheels\pip-7.0.1-py2.py3-none-any.whl\pip\req\req_install.py", line 1003, in move_wheel_files
    isolated=self.isolated,
  File "c:\Python27\lib\site-packages\virtualenv\_wheels\pip-7.0.1-py2.py3-none-any.whl\pip\wheel.py", line 266, in move_wheel_files
    compileall.compile_dir(source, force=True, quiet=True)
  File "C:\Program Files\Python 3.5\lib\compileall.py", line 88, in compile_dir
    legacy, optimize):
  File "C:\Program Files\Python 3.5\lib\compileall.py", line 126, in compile_file
    cfile = importlib.util.cache_from_source(fullname)
  File "<frozen importlib._bootstrap_external>", line 267, in cache_from_source
  File "<frozen importlib._bootstrap_external>", line 58, in _path_split
NameError: name 'path_separators' is not defined

Any idea what's going on? Should I try to make a minimal reproducing example?