'Ensure an invalid operator returns a Bad Request.
GET /users?password_expires_at={invalid_operator}:{timestamp}
GET /users?password_expires_at={operator}:{timestamp}&
{invalid_operator}:{timestamp}'

def test_list_users_by_password_expires_with_bad_operator_fails(self):

    bad_op_url = self._list_users_by_password_expires_at(self._format_timestamp(self.starttime), 'x')
    self.get(bad_op_url, expected_status=http_client.BAD_REQUEST)
    bad_op_url = self._list_users_by_multiple_password_expires_at(self._format_timestamp(self.starttime), 'lt', self._format_timestamp(self.starttime), 'x')
    self.get(bad_op_url, expected_status=http_client.BAD_REQUEST)
