code: def check(self, request, response, secret):
          
          auth = request.get_header('Authorization')
          if auth == '':
              raise KeyError('Authorization header is required for the request.')
          ah = self.orig.parse_auth_headers(auth)
          act = response.headers['X-Server-Authorization-HMAC-SHA256']
          if act == '':
              raise KeyError('Response is missing the signature header X-Server-Authorization-HMAC-SHA256.')
          sig = self.sign(request, ah, response.text, secret)
          return sig == act
docs: Checks the response for the appropriate signature. Returns True if the signature matches the expected value.
  
          Keyword arguments:
          request -- A request object which can be consumed by this API.
          response -- A requests response object or compatible signed response object.
          secret -- The base64-encoded secret key for the HMAC authorization.