Copied from the issue:
I’m guessing that you’re passing in a tuple that doesn’t look like (torch.ones(2, 2),). For a Tuple the type needs to be fixed and completely specified and the elements can be different types. In TorchScript, a, b, and c below are all different types
# type is `Tuple[int, int, int]
a = (1, 2, 3)

# type is `Tuple[str, int, int]
b = ('hi', 2, 3)

# type is `Tuple[int]`
c = (2,)

For lists, the element types must all be the same, which is why it can be any length but you only need to specify List[Tensor] or List[int]. You can read more about it here 6.