from __future__ import annotations from typing import Callable from mypy.plugin import FunctionContext, Plugin from mypy.types import Type class Plugin2(Plugin): def get_function_hook(self, fullname: str) -> Callable[[FunctionContext], Type] | None: if fullname in ("__main__.f", "__main__.g"): return str_hook return None def str_hook(ctx: FunctionContext) -> Type: return ctx.api.named_generic_type("builtins.str", []) def plugin(version: str) -> type[Plugin2]: return Plugin2