Question

The following seems not to be valid in python 3:

class A:
 callback = A.callback_function

 def callback_function(self):
  pass

You’ll get an error saying type ‘A’ is not defined. Is it because ‘A’ cannot be refered to in it self? Is there anyway I can achieve this type of functionality?

What I’m trying to do is something like this: I have a base class:

class Base:
 callback = Base.ignore

 def ignore(self):
  pass

 def some_other_function(self):
  self.callback()

In a subclass I’d like to set another callback function:

class Derived(Base):
 callback = Derived.special_function

 def special_function(self):
  do_stuff()

Answer 1

Well, you can just name your function callback, and it’ll be just the same, but if you really insist on this way:

class A:
    def callback_function(self): pass

    callback = callback_function