def METHOD_NAME(self):
    self.validator.client_authentication_required.return_value = False
    self.validator.authenticate_client_id.return_value = False
    body = urlencode([('token', 'foo'),
                      ('token_type_hint', 'access_token')])
    h, b, s = self.endpoint.create_introspect_response(self.uri,
            headers=self.headers, body=body)
    self.assertEqual(h, {
        'Content-Type': 'application/json',
        'Cache-Control': 'no-store',
        'Pragma': 'no-cache',
        "WWW-Authenticate": 'Bearer error="invalid_client"'
    })
    self.assertEqual(loads(b)['error'], 'invalid_client')
    self.assertEqual(s, 401)