Why does Threading.Timer 'function' expect None as return type? #3782
Description
The Timer signature specifies that function should have the signature Callable[..., None]. I couldn't find anything in the official Timer documentation on why that would be. In my project I found myself using a function with return value (that I'm not interested in), and don't see why this should not be accepted usage. I think probably the correct signature should be Callable[..., Any]. Could someone clarify?