Python: self.__class__ vs. type(self) [duplicate]

Answer 1

As far as I am aware, the latter is just a nicer way of doing the former.

It's actually not that unusual in Python, consider repr(x), which just calls x.__repr__() or len(x), which just calls x.__len__(). Python prefers to use built-ins for common functions that you are likely to use over a range of classes, and generally implements these by calling __x__() methods.

Answer 2

>>> class Test(object): pass
>>> t = Test()
>>> type(t) is t.__class__
True
>>> type(t)
__main__.Test

So those two are the same. I would use self.__class__ since it's more obvious what it is.

However, type(t) won't work for old-style classes since the type of an instance of an old-style class is instance while the type of a new-style class instance is its class:

>>> class Test(): pass
>>> t = Test()
>>> type(t) is t.__class__
False
>>> type(t)
instance