[Python] Create Literal type from constant variables

I want to use "constant" variables in my typing definitions, something like this:

FOO = "foo"
BAR = "bar"

@dataclass
class Event():
name: Literal[FOO, BAR]


But that is illegal code for mypy.

This works, but then I cannot use the variables in my code:

FOO = Literal["foo"]
BAR = Literal["bar"]

@dataclass
class Event():
name: FOO | BAR

Event(FOO) # gives: Event(name=typing.Literal['foo'])


Is there a way to get this to work without defining FOO and BAR twice?


Impelenting Marks answer (https://stackoverflow.com/a/76382060/5386216) works, but then mypy is not able to distinguish types based on the event name:

class FooBar(Enum):
FOO = "foo"
BAR = "bar"

@dataclass
class StringEvent:
name: Literal[FooBar.FOO]
value: str


@dataclass
class NumberEvent:
name: Literal[FooBar.BAR]
value: int


def handle_event(event: StringEvent | NumberEvent):
if event.name == FooBar.FOO:
event.value.upper() # should not give a mypy error

if event.name == FooBar.BAR:
event.value.upper() # Should give a mypy error


Both both cases of event.value.upper() give the following mypy error: Item "int" of "Union[str, int]" has no attribute "upper"

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