Image Segmentation Class weight using tensorflow keras

I remember definitely being able to pass a list to class_weight with keras (binary image segmentation specifically). For example:

class_weight = [1, 10] (1:10 class weighting)

But now it’s saying it has to take a dictionary instead of a list.

weights = {0: 1, 1: 10}

Well, when I do that I get the error:

`class_weight` not supported for 3+ dimensional targets.

Has something changed? I didn’t think I’d have so many issues here.