Does Python have class prototypes (or forward declarations)?

Question

I have a series of Python classes in a file. Some classes reference others.

My code is something like this:

class A():
    pass

class B():
    c = C         


        

Answer 1

Python doesn't have prototypes or Ruby-style open classes. But if you really need them, you can write a metaclass that overloads new so that it does a lookup in the current namespace to see if the class already exists, and if it does returns the existing type object rather than creating a new one. I did something like this on a ORM I write a while back and it's worked very well.