Log Message:
py-fakefs: updated to 3.5.8

Version 3.5.8
Another bug-fix release that mainly fixes a regression wih Python 2 that has \ 
been introduced in version 3.5.3.

Fixes
regression: patching build-in open under Python 2 broke unit tests
fixed writing to file added with add_real_file
fixed argument name of FakeIOModule.open

Infrastructure
more changes to run tests using python setup.py test under Python 2 regardless \ 
of pathlib2 presence