Description
I want define a generic class which is covariant with its type parameter, but mypy claims that covariant type parameter in instance method definition is not allowed.
from typing import Generic, List, TypeVar
T = TypeVar("T", covariant=True)
class GenericClass(Generic[T]):
def __init__(self) -> None:
self.list: List[T] = []
def print(self, arg: T) -> None: # <<< mypy raises error on the "T"; Cannot use a covariant type variable as a parameter
self.list.append(arg)
print(self.list)
if __name__ == "__main__":
g: GenericClass[int] = GenericClass()
g.print(1)Is there any solution to get around this?