Converting Python dict to class init **kwargs?

Asked Apr 17 '20 at 09:33

Active Apr 17 '20 at 09:42

Viewed 54 times

I want to create two instance of class , and send dict to init , but why the first class instance reference second class dict ?

class Test:

    def __init__(self, *args, **kwargs):
        print(kwargs)
        self.k = kwargs


initDict = {'PP':{'a':1}}
newC1 = initDict.copy()
newC1['PP']['b'] = 2
qq1 = Test(**newC1)

newC2 = initDict.copy()
newC2['PP']['b'] = 999
qq2 = Test(**newC2)

print('---------------')
print(qq1.k)
print(qq2.k)

there is the result

{'PP': {'a': 1, 'b': 2}}
{'PP': {'a': 1, 'b': 999}}
---------------
{'PP': {'a': 1, 'b': 999}}
{'PP': {'a': 1, 'b': 999}}

asked Apr 17 '20 at 09:33

Relax ZeroC

3

`initDict.copy()` is a shallow copy. The nested dict isn't copied. – user2357112 Apr 17 '20 at 09:35
^This. Try comparing id of newC1 and newC2 (different, because `.copy()`) and id of newC1['PP'] and newC2['PP'] (same, nested dict is kept the same way) – h4z3 Apr 17 '20 at 09:45
@user2357112supportsMonica there must be an appropriate duplicate for this. – juanpa.arrivillaga Apr 17 '20 at 09:45
1

@user2357112supportsMonica is right. Take a look at [this answer](https://stackoverflow.com/questions/5105517/deep-copy-of-a-dict-in-python) and deepcopy your `initDict` – Teshan Shanuka J Apr 17 '20 at 09:56

Converting Python dict to class __init__ **kwargs?

0 Answers0

Converting Python dict to class init **kwargs?