[Python] How to properly type-hint a Python dict whose keys are Type[T] and values are...

I'd like to have a dict hinted such that the values contain generics of a type that's the same as the key:

from abc import ABC
from typing import Dict, List, Type, TypeVar

class Event(ABC):
pass

class MessageReceived(Event):
pass

class MessageSent(Event):
pass

EventT = TypeVar("EventT", bound=Event)

events: Dict[Type[EventT], List[EventT]] = {}



mypy returns an error along the lines of:

Type variable "EventT" is unbound [valid-type]


I understand why EventT is unbound, but I cannot work out a way to actually hint this properly.

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