Python doesn't really support mixed spaces and tabs well, and in python3
upstream finally did the sensible thing and made mixed tab and space
indents a runtime error.

This patch was generated with the following command on Linux:
find . -name '*py' | xargs sed -i -e 's@\t@        @g'

It was then hand edited to fix whitespace errors introduced by tabs not
being 8 spaces.

Signed-off-by: Dylan Baker <baker.dylan.c@gmail.com>