def __missing__(self, key):
        if self.default_factory is None:
            raise KeyError(key)
        else:
            ret = self[key] = self.default_factory(name=key)
            return ret
def test_bad_url_error_message():
    values = [
        'google.com',
        'domain.google.com',
        'kevin:pass@google.com/path?query',
        u'google.com/path?\u2713',
    ]

    for value in values:
        yield check_url_error_message, value