[Python] How to annotate dict-like object with key-value structure in Python?

Let's say that I have a class like:

from typing import Any

class A:
def __init__(self, *args):
self.items: list[int] = list(args)

def __getitem__(self, k: str):
v = int(k)
if v in self.items:
return v
return None

def __setitem__(self, k: str, _: Any = None):
v = int(k)
print(f'Value {_} is not important')
if v not in self.items:
self.items.append(int(k))


Elements of the class are accessible by object[element_name] syntax. And it is obvious that value of element will be an integer:

a = A(1, 2, 3)
a['4'] = 'Something'

print(a['2'])
# 2
print(a['4'])
# 4


Annotation for a dictionary with the same behavior will be like dict[str, int]. Where key is str and value is int. But how to annotate these generic types for custom objects?

Because A[str, int] is not working.

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