required steps to run container properly

it would be really helpful to make it explicit that the following lines are necessary to run the container properly

`connector = FunctionConnector()` and

`if __name__ == "__main__":
start(connector)`

https://github.com/hasura/ndc-python-lambda/blob/4cb6f2a78ba2b335fa20077373355ccb3a08e4fc/connector-definition/template/functions.py#L19

thank you!