[Python] Collecting return types from vararg Callable for use elsewhere in signature?

I have the following function signature:

Y = Annotated[TypeVar("Y"), "That which might be yielded"]
R = Annotated[TypeVar("R"), "That which might be returned"]

def teeinto_constantmemory(
it: Iterable[Y],
*consumer_callables: Callable[[Iterable[Y]], R]
) -> Tuple[R, ...]: ...


This function signature is obviously inadequate.

1. 
   It doesn't indicate that the length of the return value is equal to the quantity of consumer_callables.
   
   
2. 
   Further, it doesn't indicate that the n-th element of the return tuple has the same type as the return type of the n-th element of consumer_callables (especially when the callables return different types from each other).
   

I already checked out PEP 646, but the closest section they had to relevant was “Type Variable Tuples with Callable”, which I couldn't see how to apply to this situation.

Have I missed the solution, or is this use-case actually not yet addressed by Python's type hinting ecosystem?


For example, if you call the function with five positional arguments, of types

1. 
   Iterable
   
   
2. 
   Callable[[Iterable], int]
   
   
3. 
   Callable[[Iterable], float]
   
   
4. 
   Callable[[Iterable], str]
   
   
5. 
   Callable[[Iterable], FooType]
   

then the return value will be of type

• Tuple[int, float, str, FooType]

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