Log Message:
py-pathlib2: updated to 2.3.7.1

Version 2.3.7-post1

Drop minimum required six version for the love of good old pip under Python 2, \ 
and updated code to be compatible with older six versions. Previous 2.3.7 \ 
releases were yanked to avoid potential issues.

Version 2.3.7-post0

Set minimum required six version.