[Python] Dynamically create Literal alias from list of valid values

I have a function which validates its argument to accept only values from a given list of valid options. Typing-wise, I reflect this behavior using a Literal type alias, like so:

from typing import Literal


VALID_ARGUMENTS = ['foo', 'bar']

Argument = Literal['foo', 'bar']


def func(argument: 'Argument') -> None:
if argument not in VALID_ARGUMENTS:
raise ValueError(
f'argument must be one of {VALID_ARGUMENTS}'
)
# ...


This is a violation of the DRY principle, because I have to rewrite the list of valid arguments in the definition of my Literal type, even if it is already stored in the variable VALID_ARGUMENTS. How can I create the Argument Literal type dynamically, given the VALID_ARGUMENTS variable?

The following things do not work:

from typing import Literal, Union, NewType


Argument = Literal[*VALID_ARGUMENTS] # SyntaxError: invalid syntax

Argument = Literal[VALID_ARGUMENTS] # Parameters to generic types must be types

Argument = Literal[Union[VALID_ARGUMENTS]] # TypeError: Union[arg, ...]: each arg must be a type. Got ['foo', 'bar'].

Argument = NewType(
'Argument',
Union[
Literal[valid_argument]
for valid_argument in VALID_ARGUMENTS
]
) # Expected type 'Type[_T]', got 'list' instead


Can it be done at all?

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