python setup.py test -v doesn't work

↪ python setup.py test -v
running test
Traceback (most recent call last):
File "setup.py", line 781, in <module>
setup(**args)
File "/usr/lib/python3.6/distutils/core.py", line 148, in setup
dist.run_commands()
File "/usr/lib/python3.6/distutils/dist.py", line 955, in run_commands
self.run_command(cmd)
File "/usr/lib/python3.6/distutils/dist.py", line 974, in run_command
cmd_obj.run()
File "setup.py", line 124, in run
testresult = t.run(tests)
File "/usr/lib/python3.6/unittest/runner.py", line 153, in run
result = self._makeResult()
File "/usr/lib/python3.6/unittest/runner.py", line 149, in _makeResult
return self.resultclass(self.stream, self.descriptions, self.verbosity)
File "/usr/lib/python3.6/unittest/runner.py", line 40, in _init_
self.showAll = verbosity > 1
TypeError: '>' not supported between instances of 'str' and 'int'