code: def _compute_weights(cls, stack_height: int, alpha: jax.Array):
      forward = [(alpha, alpha)]
      backward = [(stack_height * alpha, stack_height * alpha)]
      for i in range(2, stack_height + 1):
          a, b = forward[-1]
          forward.append((a * i * alpha, (b + 1) * i * alpha))
          j = stack_height - i + 1
          a, b = backward[-1]
          backward.append((a * j * alpha, (b + 1) * j * alpha))
      return forward, backward
  
imports: import functools
  import re
  from typing import Optional
  from absl.testing import absltest
  from absl.testing import parameterized
  from haiku._src import base
  from haiku._src import basic
  from haiku._src import config
  from haiku._src import initializers
  from haiku._src import layer_stack
  from haiku._src import module
  from haiku._src import multi_transform
  from haiku._src import transform
  from haiku._src import utils
  import jax
  import jax.numpy
  import numpy
  from scipy import stats
label_desc: Use image node_id 13 for calling the LayerStackTest obj's underlying member method code with example usage: obj._compute_weights(cls, stack_height, alpha) and returns: forward,  backward