code: def enumerate(semiring, scores):
      terms, rules, roots = scores
      batch, N, T = terms.shape
      _, NT, _, _ = rules.shape
  
      def enumerate(x, start, end):
          if start + 1 == end:
              yield (terms[:, start, x - NT], [(start, x - NT)])
          else:
              for w in range(start + 1, end):
                  for y in (
                      range(NT) if w != start + 1 else range(NT, NT + T)
                  ):
                      for z in (
                          range(NT)
                          if w != end - 1
                          else range(NT, NT + T)
                      ):
                          for m1, y1 in enumerate(y, start, w):
                              for m2, z1 in enumerate(z, w, end):
                                  yield (
                                      semiring.times(
                                          semiring.times(m1, m2),
                                          rules[:, x, y, z],
                                      ),
                                      [(x, start, w, end)] + y1 + z1,
                                  )
  
      ls = []
      for nt in range(NT):
          ls += [
              semiring.times(s, roots[:, nt])
              for s, _ in enumerate(nt, 0, N)
          ]
      return semiring.sum(torch.stack(ls, dim=-1)), None
  
imports: import torch_struct
  import torch
  from torch_struct import LogSemiring
  import itertools
  from hypothesis.strategies import integers, composite, floats
  from hypothesis.extra.numpy import arrays
  import numpy
label_desc: Use image node_id 2 for calling the CKYTest obj's underlying member method code with example usage: obj.enumerate(semiring, scores) and returns: semiring,  None