'When the command is missing certain arguments, it should
raise an exception'

@ddt.data(['--email', 'foo'], ['--course', 'bar'], ['--bad-param', 'baz'])
def test_not_enough_args(self, arg):

    command_args = arg
    with self.assertRaises(CommandError):
        call_command('enroll_user_in_course', *command_args)
