[Python] How can I provide type hints while destructuring my class

I would like to create a class that looks something like ConfigAndPath:

import pathlib
from typing import TypeVar, Generic
from dataclasses import dataclass, astuple

class ConfigBase:
pass
T = TypeVar("T", bound=ConfigBase)

@dataclass
class ConfigAndPath(Generic[T]):
path: pathlib.Path
config: T


I often have a list of these ConfigAndPath, and so would want to destructure it in list comprehensions like this:

l: list[ConfigAndPath[MyConfig]] = ...
filenames = [_path.name for _path, _my_config in l]


So I added an __iter__ method to my class:

# In ConfigAndPath
def __iter__(self):
return iter(astuple(self))


However, I'm not sure how to make it so that my typechecker (Pyright) realizes that _path is a pathlib.Path and _my_config is a MyConfig. This works with NamedTuple, however I can't appear to use generics with NamedTuple due to it not allowing multiple inheritance. Is this possible to specify what I want?

I tried writing an as_tuple method:

# In ConfigAndPath
def as_tuple(self) -> Tuple[pathlib.Path, T]:
return self.path, self.config


Which then allows me to write

filenames2 = [_path.name for _path, _my_config in [i.as_tuple() for i in l]]


Which gives me a type hint but is quite verbose and walks the list twice.

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