code: def get_subtree_proof_nodes(
      chunk_index_groups: Sequence[Tuple[int, ...], ...],
  ) -> Tuple[int, ...]:
      subtree_node_paths = (
          # We take a candidate element from each group and shift it to
          # remove the bits that are not common to other group members, then
          # we convert it to a tree path that all elements from this group
          # have in common.
          chunk_index
          for chunk_index, bits_to_truncate
          # Each group will contain an even "power-of-two" number of# elements.
          # This tells us how many tailing bits each element has# which need to
          # be truncated to get the group's common prefix.
          in (
              (group[0], (len(group) - 1).bit_length())
              for group in chunk_index_groups
          )
      )
      return subtree_node_paths
  
label_desc: Use image node_id 2 for calling a global function with example usage: get_subtree_proof_nodes(chunk_index_groups) and returns: subtree_node_paths