def clean_semver(cls, version_spec):
        return re.sub(r"([<>=~])\s+?v?", "\\1", version_spec, re.IGNORECASE)
def test_optional_arguments(self):
        self.assertEqual(self.myfunc('a'), self.expected)
        self.assertEqual(self.myfunc('a', 5), self.expected)
        self.assertEqual(self.myfunc('a', second=5), self.expected)
        self.assertEqual(self.myfunc('a', 5, 5), self.expected)
        self.assertEqual(self.myfunc('a', fourth=[]), self.expected)