code: def generate_confirmation_key(identity_secret, tag, timestamp):
      
      data = struct.pack('>Q', int(timestamp)) + tag.encode('ascii') # this will NOT stop working in 2038
      return hmac_sha1(bytes(identity_secret), data)
docs: Generate confirmation key for trades. Can only be used once.
  
      :param identity_secret: authenticator identity secret
      :type identity_secret: bytes
      :param tag: tag identifies what the request, see list below
      :type tag: str
      :param timestamp: timestamp to use for generating key
      :type timestamp: int
      :return: confirmation key
      :rtype: bytes
  
      Tag choices:
  
          * ``conf`` to load the confirmations page
          * ``details`` to load details about a trade
          * ``allow`` to confirm a trade
          * ``cancel`` to cancel a trade