dict type hints should only take 1 or 2 inputs

[randolf-scholz]

It is weird that it is allowed to write something like dict[str, int, float] without raising an error.

A suggestion:

• dict ⇝ dict[Any, Any]
• dict[key_type] ⇝ dict[key_type, Any]
• dict[key_type, value_type]
• dict[...] with ≥3 arguments raises Error.

[erictraut]

Type checkers like mypy or pyright will generate an error if you supply too many type arguments. The Python runtime doesn't enforce this because generic types are erased at runtime.