You do not have Python 3.6 installed locally and you do not wish to install an unsupported version of Python.
Approach
Run nose2pytest on Python 3.6 on Docker to get the conversion pull request started and then finish that PR outside of Docker where your editing tools will be better.
This approach was used to create xlcnd/isbnlib#108 and xlcnd/isbntools#119
@nicoddemus
Workaround until #15 is fixed.
Upgrade Python tests from nose to pytest by running nose2pytest on Python 3.6 on Docker
Assumptions
15
Approach
This approach was used to create xlcnd/isbnlib#108 and xlcnd/isbntools#119 @nicoddemus