`typing_extensions.Final` cannot be used for dataclasses.

final.py

from __future__ import annotations

from typing_extensions import Final

from dataclasses import dataclass


@dataclass
class A:
    x: Final[int] = 100
    # x: Final[int] # error: Final name must be initialized with a value


class B:
    x: Final[int]

    def __init__(self, x: int) -> None:
        self.x = x


a = A(200)

# error: Cannot assign to final attribute "x"
# a.x = 20

print(a) # A(x=200)