I'm not sure what you mean by "cannot be understood well". Either the type annotation is correct or not. If there is a genuine bug in mypy, the recommended co

I'm not sure what you mean by "cannot be understood well". Either the type annotation is correct or not. If there is a genuine bug in mypy, the recommended convention is to use "type: ignore" (ideally with a reference to a bug tracking id). If you are genuinely subverting the typesystem, then use a cast(). If the code is too complex to type correctly or the type cannot be expressed in the typesystem (e.g. recursive types) then use type Any.