code: def verify(self, msg, sig, key):
          
          try:
              h = hmac.HMAC(key, self.algorithm(), default_backend())
              h.update(msg)
              h.verify(sig)
              return True
          except:
              return False
docs: Verifies whether sig is the correct message authentication code of data.
  
          :param msg: The data
          :param sig: The message authentication code to verify against data.
          :param key: The key to use
          :return: Returns true if the mac was valid otherwise it will raise an
              Exception.