Lately, I was looking at some Python idioms.
I found many descriptions of protocols used in Python, such as the ordering (__cmp__, ...) or generators. Besides, there are also methods like __hash__ which are defined for every object (I suppose).
After some search on the internet, I haven't found a comprehensive list of these protocols and methods.
Can anyone give me some pointers URLs?
Your best reference is always going to be the Python Online Documentation, specifically the section on Special method names.
The interactive Python interpretor is a very useful tool, too. Try some of these:
>>> dir(object)
['__class__', '__delattr__', '__doc__', '__eq__', '__format__', '__ge__', '__getattribute__', '__gt__', '__hash__', '__init__', '__le__', '__lt__', '__ne__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__']
>>> help(object.__class__)
>>> help(object.__hash__)
>>> help(hash)