Issue Using Deepcopy With Dictionary Inside Object

Reading the documentation, I understood that copy.deepcopy(obj) copies recursively any other object inside this one, but when I run: >>> import copy >>> class Som

Solution 1:

Deepcopy only copies instance attributes. Your b attribute is a class attribute, instead.

Even if you did not create a copy but a new instance of SomeObject manually, b would still be shared:

>>> class SomeObject:
...     a=1
...     b={1:1,2:2}
... 
>>> so1 = SomeObject()
>>> so2 = SomeObject()
>>> so1.b is so2.b
True
>>> so1.b is SomeObject.b
True

Make b an instance attribute:

>>> import copy
>>> class SomeObject:
...     a = 1
...     def __init__(self):
...         self.b = {1: 1, 2: 2}
... 
>>> so1 = SomeObject()
>>> so2 = copy.deepcopy(so1)
>>> so1.b is so2.b
False