[Python] How to annotate classes that are created dynamically?

Based on this accepted answer, I have done:

from typing import Type


class BaseEntity:
id: str


def make_new_entity(name: str, attrs: dict) -> Type[BaseEntity]:
return type("RuntimeEntity", (BaseEntity,), attrs)


RuntimeEntity: Type[BaseEntity] = make_new_entity("RuntimeEntity", {"id": "entity.RuntimeEntity"})

# My code from here

class Foo:
entity_instances: list[RuntimeEntity] # <- Here, linter is yelling at me
other_entity_instances: list["RuntimeEntity"] # <- Same, linter is yelling at me




I have :

• from Pylance Variable not allowed in type expression PylancereportInvalidTypeForm
• from mypy error: Variable "foo.RuntimeEntity" is not valid as a type [valid-type]

Why ? What is the correct what to annotate a class created dynamically?

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