[Python] Is it possible to type annotate Python function parameter used as TypedDict key to...

While working through code challenges I am trying to use type annotations for all function parameters/return types. I use mypy in strict mode with the goal of no errors.

I've spent some time on this one and can't figure it out - example of problem:

from typing import Literal, NotRequired, TypedDict

class Movie(TypedDict):
Title: str
Runtime: str
Awards: str

class MovieData(TypedDict):
Awards: NotRequired[str]
Runtime: NotRequired[str]

def get_movie_field(movies: list[Movie], field: Literal['Awards', 'Runtime']) -> dict[str, MovieData]:
return {movie['Title']: {field: movie[field]} for movie in movies}


# Check with mypy 1.14.0:
PS> mypy --strict .\program.py
program.py:13: error: Expected TypedDict key to be string literal [misc]
Found 1 error in 1 file (checked 1 source file)


Is there some way to make this work? I realize I can append # type: ignore to the line but I'm curious if there's another way.

I've tried a bunch of different permutations such as ensuring field matches one of the literal values before the dict comprehension but nothing seems to help.

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