I used Sven Marnach's answer to overwrite my class. But some methods or values in 'super' or 'super-of-super' class were missing, depending on executing __class__ or __dict__ lines.
This is a simple code that represents the problem.
class Grand:
def __init__(self, num):
self.g = num
def gg(self):
print("Grand:", self.g)
class Parent(Grand):
def __init__(self, num):
super().__init__(num)
self.p = num
def pp(self):
print("Parent:", self.p)
print("Grand:", self.g)
class Child(Grand):
def __init__(self, A, B, C):
A.p = A.p - B.p - C.p
self.__class__ = A.__class__ ###!!!
self.__dict__ = A.__dict__ ###!!!
def cc(self):
print("New value:", self.p)
p1 = Parent(100)
p2 = Parent(20)
p3 = Parent(30)
c = Child(p1, p2, p3)
print(dir(c))
### Both __class__ and __dict__ updated: 'cc' mising ###
['__class__', '__delattr__', '__dict__', '__dir__', '__doc__', '__eq__', '__format__', '__ge__', '__getattribute__', '__gt__', '__hash__', '__init__', '__init_subclass__', '__le__', '__lt__', '__module__', '__ne__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__', '__weakref__', 'g', 'gg', 'p', 'pp']
Traceback (most recent call last):
File "toy.py", line 28, in <module>
c.cc()
AttributeError: 'Parent' object has no attribute 'cc'
### Only __class__ updated: 'pp' missing ###
['__class__', '__delattr__', '__dict__', '__dir__', '__doc__', '__eq__', '__format__', '__ge__', '__getattribute__', '__gt__', '__hash__', '__init__', '__init_subclass__', '__le__', '__lt__', '__module__', '__ne__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__', '__weakref__', 'cc', 'g', 'gg', 'p']
New value: 50
### Only __dict__ updated: 'g', 'p', 'cc' missing ###
['__class__', '__delattr__', '__dict__', '__dir__', '__doc__', '__eq__', '__format__', '__ge__', '__getattribute__', '__gt__', '__hash__', '__init__', '__init_subclass__', '__le__', '__lt__', '__module__', '__ne__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__', '__weakref__', 'gg', 'pp']
Traceback (most recent call last):
File "toy.py", line 28, in <module>
c.cc()
AttributeError: 'Parent' object has no attribute 'cc'
### No updated 'g', 'p', 'pp' missing ###
['__class__', '__delattr__', '__dict__', '__dir__', '__doc__', '__eq__', '__format__', '__ge__', '__getattribute__', '__gt__', '__hash__', '__init__', '__init_subclass__', '__le__', '__lt__', '__module__', '__ne__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__', '__weakref__', 'cc', 'gg']
Traceback (most recent call last):
File "toy.py", line 28, in <module>
c.cc()
File "toy.py", line 21, in cc
print("New value:", self.p)
AttributeError: 'Child' object has no attribute 'p'
What are the proper ways to update all values: 'g', 'p' and methods: 'pp', 'gg', 'cc'?
