fixes issue #678 Incorrect diff markup when diff contains >, <, or & symbols - regex by \W did split & and other to 3 tokens, and escaping was broken
"""Various utilities to work with Python < 2.7.Those utilities may be deleted once ``vcs`` stops support for older Pythonversions."""importsysifsys.version_info>=(2,7):unittest=__import__('unittest')else:unittest=__import__('unittest2')