assign a value to a dict change all the values

[aster]

You can't assign to a tuple index, so it won't work. This is an important point in Python. Mutables, like lists, dictionaries, and sets, display the behavior you see above. Immutables, like numbers, strings, and tuples, do not.

yes i know, what i wanted to check is if i can change the item pointed by a reference

from copy import deepcopy

x = [1, 2, 3]
y = (x, 4, 5)
print(y)

z = deepcopy(y)
x[1] = 7
print(y)
print(z)

and i can, please tell me if i am wrong: i can change it because the reference of 'x' inside y is always the same
but so which is the difference between a normal copy and a shallow copy?
i am almost sure that i understood correctly the difference between a copy and a deep copy, the last one is completely a new object while the first is a reference to the original object