def remove(self, elem):
        """Remove a requirement.

        :param elem: a string or :class:`Requirement` instance.
        """
        if isinstance(elem, text_type):
            for requirement in self:
                if requirement.package == elem:
                    return super(Requirements, self).remove(requirement)
        return super(Requirements, self).remove(elem)
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