from . import _OnSetAttrType, Attribute from typing import TypeVar, Any, NewType, NoReturn, cast _T = TypeVar("_T") def frozen( instance: Any, attribute: Attribute, new_value: Any ) -> NoReturn: ... def pipe(*setters: _OnSetAttrType) -> _OnSetAttrType: ... def validate(instance: Any, attribute: Attribute[_T], new_value: _T) -> _T: ... # convert is allowed to return Any, because they can be chained using pipe. def convert( instance: Any, attribute: Attribute[Any], new_value: Any ) -> Any: ... _NoOpType = NewType("_NoOpType", object) NO_OP: _NoOpType