AttributeError: 'Version' object has no attribute 'major'

Hello,

I am very new to Python and I saw a similar issue discussed here https://github.com/dephell/dephell_specifier/issues/9

I am trying to run pyfolio and getting AttributeError: 'Version' object has no attribute 'major'

I tried pip install --user dephell_specifier to update, however it did not solve an issue.

I would be very grateful if you can give me any advise on how to solve it since I cannot find anything on the web.

My system version is sys.version_info(major=3, minor=7, micro=4, releaselevel='final', serial=0)

Thank you