Just want to know what's the common way to react on events in python. There are several ways in other languages like callback functions, delegates, listener-structures and so on. 
Is there a common way? Which default language concepts or additional modules are there and which can you recommend?
Personally, I've only seen callbacks used.  However, I haven't seen that much event driven python code so YMMV.
Python: Callbacks, Delegates, ... ? What is common?