Bug Report

Type check is ignored on keys and values of a dictionary when declared in a specific way.

To Reproduce

playground example

Mypy detects the error whenever Util.constructor or Util.apply is not used. But if both are used the calls to f used on the keys or values are not type checked.

Expected Behavior
error: Argument 1 has incompatible type "str"; expected "int" [arg-type] at the calls of f

Actual Behavior

Mypy does not throw arg-type errors
Your Environment

checkout playground example