Import error on macos

[damonbrodie]

If I do:

Import html5lib

on my mac (python 2.7)

I get the following:

Traceback (most recent call last): File "./test2.py", line 2, in <module> import html5lib File "build/bdist.macosx-10.12-intel/egg/html5lib/__init__.py", line 16, in <module> File "build/bdist.macosx-10.12-intel/egg/html5lib/html5parser.py", line 2, in <module> ImportError: cannot import name viewkeys

[gsnedders]

That's an out-of-date six, if you update six it should work; see also #301.