[Python] Pyright doesn't understand implementation of protocols [duplicate]

In my code base I have many declarations like this:

from typing import Protocol, override
from dataclasses import dataclass

# Definition of protocols (usually in a separate file)

@dataclass
class Data(Protocol):
val: int = 1

class Programm(Protocol):

def update(self, data: Data) -> int: ...

# Concrete implementation of the protocols:

@dataclass
class DataA(Data):
val_concrete: int = 2


class ProgrammA(Programm):

@override
def update(self, data: DataA) -> int:
return data.val_concrete + data.val


I was confident that this is the right way to use protocols. Maybe I am mistaken. When I turn on pyright (in fact I use basedpyright, but I should be the same), it marks ProgrammA.update() and complains:

[reportIncompatibleMethodOverride]: Method "update" overrides class "Programm" in an incompatible manner

Am I doing something wrong? I can get around this using a redundant generic. But I think this is unnecessary and in some way just wrong.

If my approach is correct, can I do something to clarify things in a way, pyright understands?

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