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I know what I am asking is rather niche, but it has been bugging me for quite a while. Suppose I have the following function:

python def foo(return_more: bool): .... if return_more: return data, more_data return data

You can imagine it is a function that may return more data if given a flag.

How should I typehint this function? When I use the function in both ways ``` data = foo(False)

data, more_data = foo(True) ```

either the first or the 2nd statement would say that the function cannot be assigned due to wrong size of return tuple.

Is having variable signature an anti-pattern? Is Python's typehinting mechanism not powerful enough and thus I am forced to ignore this error?

Edit: Thanks for all the suggestions. I was enlightened by this suggestion about the existence of overload and this solution fit my requirements perfectly

``` from typing import overload, Literal

@overload def foo(return_more: Literal[False]) -> Data: ...

@overload def foo(return_more: Literal[True]) -> tuple[Data, OtherData]: ...

def foo(return_more: bool) -> Data | tuple[Data, OtherData]: .... if return_more: return data, more_data return data

a = foo(False) a,b = foo(True) a,b = foo(False) # correctly identified as illegal ```