multiple subscribers/observers the output from this program iscreate the observable object set up observers subscribers lambda received lambda received lambda received lambda received function received function received function received function received object received object received object received object received data stream completed received on_next received on_next received on_next received on_next received completed notification note how each of the subscribers is sent all of the data before the next subscriber is sent their data (this is the default single threaded rxpy behaviour subjects in rxpy subject is both an observer and an observable this allows subject to receive an item of data and then to republish that data or data derived from it for exampleimagine subject that receives stock market price data published by an external (to the organisation receiving the datasource this subject might add timestamp and source location to the data before republishing it to other internal observers howeverthere is subtle difference that should be noted between subject and plain observable subscription to an observable will cause an independent execution of the observable when data is published notice how in the previous section all the messages were sent to specific observer before the next observer was sent any data at all howevera subject shares the publication action with all of the subscribers and they will therefore all receive the same data item in chain before the next data item in the class hierarchy the subject class is direct subclass of the observer class