Rasa Custom Connector

Hi Folks, I am creating a rasa Custom connector for telegram(different use) but getting a class error, telegram_custom_connector.custom_connector.MyIO where telegram_custom_connector is folder on the root with a custom_connector file there i defined the MyIo class according to the documentation RasaException: Failed to find input channel class for ‘custom_telegram’. Unknown input channel. Check your credentials configuration to make sure the mentioned channel is not misspelled. If you are creating your own channel, make sure it is a proper name of a class in a module.

Please help me with this why it is giving this error