In Python, I have the following function:

T = TypeVar("T")


def handle_func(x: int, func: Callable[[int], T]) -> T:
    return func(x)

And I can use it so:

handle_func(1, lambda x: x + 1)
handle_func(1, lambda x: x == 1)

When I run MyPy, all is good.

But… How can I add a default value to func?

When I do this:

def handle_func(x: int, func: Callable[[int], T] = lambda x: x + 1) -> T:
    return func(x)

and run MyPy I get:

error: Incompatible default for argument "func" (default has type "Callable[[int], int]", argument has type "Callable[[int], T]")  [assignment]
error: Incompatible return value type (got "int", expected "T")  [return-value]

But it works when the default is not there… How can I type this? What am I understanding incorrectly?