result of pip download Sphinx --no-binary :all:

gistfile1.txt

Collecting sphinxcontrib-websupport (from Sphinx)
  Downloading sphinxcontrib-websupport-1.0.1.tar.gz (590kB)
    100% |████████████████████████████████| 593kB 1.5MB/s
  Saved ./sphinxcontrib-websupport-1.0.1.tar.gz
    Complete output from command python setup.py egg_info:
    Traceback (most recent call last):
      File "<string>", line 1, in <module>
      File "/Users/ericg/py36env/lib/python3.6/site-packages/setuptools/__init__.py", line 10, in <module>
        from setuptools.extern.six.moves import filter, filterfalse, map
      File "/Users/ericg/py36env/lib/python3.6/site-packages/setuptools/extern/__init__.py", line 1, in <module>
        from pkg_resources.extern import VendorImporter
      File "/Users/ericg/py36env/lib/python3.6/site-packages/pkg_resources/__init__.py", line 3017, in <module>
        @_call_aside
      File "/Users/ericg/py36env/lib/python3.6/site-packages/pkg_resources/__init__.py", line 3003, in _call_aside
        f(*args, **kwargs)
      File "/Users/ericg/py36env/lib/python3.6/site-packages/pkg_resources/__init__.py", line 3045, in _initialize_master_working_set
        dist.activate(replace=False)
      File "/Users/ericg/py36env/lib/python3.6/site-packages/pkg_resources/__init__.py", line 2577, in activate
        declare_namespace(pkg)
      File "/Users/ericg/py36env/lib/python3.6/site-packages/pkg_resources/__init__.py", line 2151, in declare_namespace
        _handle_ns(packageName, path_item)
      File "/Users/ericg/py36env/lib/python3.6/site-packages/pkg_resources/__init__.py", line 2091, in _handle_ns
        _rebuild_mod_path(path, packageName, module)
      File "/Users/ericg/py36env/lib/python3.6/site-packages/pkg_resources/__init__.py", line 2120, in _rebuild_mod_path
        orig_path.sort(key=position_in_sys_path)
    AttributeError: '_NamespacePath' object has no attribute 'sort'

    ----------------------------------------
Command "python setup.py egg_info" failed with error code 1 in /private/var/folders/5m/816qzv6d1xv_my9nn2vr3q100000gn/T/pip-build-7b27cmiy/sphinxcontrib-websupport/