This does not work 😕
There is no files in coverage report from mpl_toolkits, file count is the same and coverage not changed. I think it is because of this line.
But even with such fix coverage report will be fooled, because nose does not report uncovered files (you can compare with this report from pytest-cov)

I think @Kojoley is right. I setup the original coverage but there are lots of issues with it and I have been postponing to change it until we have converted to pytest

Ahh... OK, let's just wait for the conversion to pytest first then.