I have a couple of {{{TypedDict}}}s for use in type hinting that are supposed to have some sets of incompatible keys. For example, if I need to specify that a particular {{{dict}}} can have {{{bar}}} or {{{baz}}} but not both of them, I can write two {{{TypedDict}}}s: {{{#!highlight python from typing import TypedDict class Foo1(TypedDict): bar: str class Foo2(TypedDict): baz: int Foo = Foo1 | Foo2 foo_instance_1: Foo = { # Works fine 'bar': 'foobar' } foo_instance_2: Foo = { # Also fine 'baz': 42 } foo_instance_3: Foo = { # Warning: Expected type 'Foo1 | Foo2', got 'dict[str, str | int]' instead 'bar': 'foobar', 'baz': 42 } }}} However, this doesn't scale very well if I were to have multiple sets; for example, a simple multiplication shows that three sets of 2, 3 and 4 keys each will result in 24 {{{TypedDict}}}s. A solution would be: {{{#!highlight python class Foo(TypedDict): bar: IncompatibleWith('baz', 'qux')[str] baz: IncompatibleWith('bar', 'qux')[int] qux: IncompatibleWith('bar', 'baz')[bool] }}} ...or, with a decorator somewhat similar to {{{@overload}}}: {{{#!highlight python @incompatible('bar', 'baz', 'qux') # ... class Foo(TypedDict): bar: str baz: int qux: bool }}} I asked this question on StackOverflow<https://stackoverflow.com/q/75981727> and was informed that such a feature doesn't exist. How about adding it to Python then?