'Check that unknown declared encodings are ignored'

def test_declared_encoding_invalid(self):

    r = self.response_class('http://www.example.com', headers={'Content-type': ['text/html;    charset=UKNOWN']}, body='\xc2\xa3')
    self.assertEqual(r._declared_encoding(), None)
    self._assert_response_values(r, 'utf-8', u'\xa3')
