[Python] How to make an easily instantiable derivative attribute-only protocol class?

I have a Protocol subclass that defines objects with attributes from an external library:

class P(Protocol):
val: int


For testing purposes, I want to turn this protocol class into something I can instantiate easily. However, when I try to turn it into a dataclass, an error pops up:

import dataclasses
from typing import Protocol

class P(Protocol):
val: int

PInst = dataclasses.dataclass(P)

PInst(val=4) # TypeError: Protocols cannot be instantiated


Is there an easy solution to use P to create a class that satifies its protocol and is instantiable, without redeclaring its attributes?

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