I really don't know how to describe this problem good enough. So i think an example is more expressive:
class A:
c=1
@staticmethod
def b(): return A.c
class B(A):
c=2
I hope B.b() returns 2. but the reality is it does not. in which way am i gonna achieve it? Thanks a lot.
The problem is that you're using a staticmethod, and hardcoding the class A, instead of using a classmethod, and using the cls argument.
Try this:
class A:
c=1
@classmethod
def b(cls): return cls.c
The docs (linked above) explain the difference, but you may want to try looking at Stack Overflow questions like What is the difference between @staticmethod and @classmethod in Python for a more in-depth discussion. Briefly: a staticmethod is basically just a global function inside the class's namespace, while a classmethod is a method on the class object; if you want to use any class attributes (or the class itself, as in the alternate constructor idiom), you want the latter.
You'd have to use a class method, so you could reference the class dynamically. A static method like you are currently using is not bound to any class, so you have to statically explicitly reference the A class as you are.
class A(object):
c = 1
@classmethod
def b(cls):
return cls.c
class B(A):
c = 2
