code: def get_packet(self, generation_time, sequence_number):
          
          url = '/archive/{}/packets/{}/{}'.format(
              self._instance, to_isostring(generation_time), sequence_number)
          response = self._client.get_proto(url)
          message = yamcs_pb2.TmPacketData()
          message.ParseFromString(response.content)
          return Packet(message)
docs: Gets a single packet by its identifying key (gentime, seqNum).
  
          :param ~datetime.datetime generation_time: When the packet was generated (packet time)
          :param int sequence_number: Sequence number of the packet
          :rtype: .Packet