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If I try to pickle and unpickle an object of a class that has specialized a generic superclass, when I try to unpickle I get this error:
TypeError: descriptor '__dict__' for 'A' objects doesn't apply to 'B' object
Test case:
from typing import Generic, TypeVar
import pickle
T = TypeVar("T")
class A(Generic[T]):
 def __init__(self, x: T):
 self.x = x
class B(A[str]):
 def __init__(self, x: str):
 self.x = x
b = B("hello")
z = pickle.dumps(b)
print(z)
_ = pickle.loads(z)