title: "This package should not be accessible on Python 3" when running python3
body: <p>I was trying to use virtualenv to switch between python versions before learning that I could use both python and python3 on my Mac.</p>
  
  <p>I was able to fix my python 2.7 version so that still works fine however, now when I run python3, I get this error:</p>
  
  <pre><code>Failed to import the site module
  Traceback (most recent call last):
    File "/usr/local/Cellar/python3/3.6.0/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site.py", line 544, in &lt;module&gt;
  main()
    File "/usr/local/Cellar/python3/3.6.0/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site.py", line 530, in main
  known_paths = addusersitepackages(known_paths)
    File "/usr/local/Cellar/python3/3.6.0/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site.py", line 282, in addusersitepackages
  user_site = getusersitepackages()
    File "/usr/local/Cellar/python3/3.6.0/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site.py", line 258, in getusersitepackages
  user_base = getuserbase() # this will also set USER_BASE
    File "/usr/local/Cellar/python3/3.6.0/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site.py", line 248, in getuserbase
  USER_BASE = get_config_var('userbase')
    File "/usr/local/Cellar/python3/3.6.0/Frameworks/Python.framework/Versions/3.6/lib/python3.6/sysconfig.py", line 601, in get_config_var
  return get_config_vars().get(name)
    File "/usr/local/Cellar/python3/3.6.0/Frameworks/Python.framework/Versions/3.6/lib/python3.6/sysconfig.py", line 580, in get_config_vars
  import _osx_support
    File "/usr/local/Cellar/python3/3.6.0/Frameworks/Python.framework/Versions/3.6/lib/python3.6/_osx_support.py", line 4, in &lt;module&gt;
  import re
    File "/usr/local/Cellar/python3/3.6.0/Frameworks/Python.framework/Versions/3.6/lib/python3.6/re.py", line 125, in &lt;module&gt;
  import functools
    File "/usr/local/Cellar/python3/3.6.0/Frameworks/Python.framework/Versions/3.6/lib/python3.6/functools.py", line 21, in &lt;module&gt;
  from collections import namedtuple
    File "/usr/local/Cellar/python3/3.6.0/Frameworks/Python.framework/Versions/3.6/lib/python3.6/collections/__init__.py", line 32, in &lt;module&gt;
  from reprlib import recursive_repr as _recursive_repr
    File "/usr/local/lib/python2.7/site-packages/reprlib/__init__.py", line 7, in &lt;module&gt;
  raise ImportError('This package should not be accessible on Python 3. '
  ImportError: This package should not be accessible on Python 3. Either you are trying to run from the python-future src folder or your installation of python-future is corrupted.
  </code></pre>
  
  <p>I've looked online for this error but most of the conversation was on fixing up the patch and then upgrading virtualenv. However, this still doesn't fix my issue.</p>
  
  <pre><code>python3 -V: Python 3.6.0
  virtualenv --version: 15.1.0
  env | egrep -i 'python|virtualenv': PYTHONPATH=/usr/local/lib/python2.7/site-packages:
  </code></pre>