The knot_weights function, from:
tensorflow_graphics.math.interpolation.bspline
requires an int for the number of knots and the degree parameters (it is mentioned in the documentation), and if a tf.constant is passed, the unhashable tensor exception will occur.
Although it is not really a bug, this seems to be a design flaw, and not expected at all (especially that other parameters are expecting tensors), since it breaks graph generation with @tf.function, unless I will convert it explicitly to int, as pointed here: tensorflow/tensorflow#27491 (comment)