http://matplotlib.org/devdocs/devel/testing.html#running-the-tests says to run

python tests.py --nocapture --nose-verbose --processes=5 --process-timeout=300

But the --nose-verbose option doesn't seem to exist!

$ python tests.py --nocapture --nose-verbose --processes=5 --process-timeout=300
Python byte-compilation optimization level: 0
Usage: tests.py [options]

tests.py: error: no such option: --nose-verbose

The options available are listed on https://nose.readthedocs.io/en/latest/usage.html#options . Just dropping the --nose-verbose option seems to be fine, but I'm not sure what was intended by whoever originally wrote that line of the docs.