code: def _combine_indexers(indexers1, indexers2):
      """Conbine index data from two indexers
      :param indexers1: list of indexers to combine index data
      :param indexers2: second list of indexers to combine index data
      :return: first list of indexers containing index data from both indexers in pair
      """
      if len(indexers1) != len(indexers2):
          raise ValueError(
              "Cannot reduce results with different dimensions"
          )
  
      return [
          indexer_pair[0] + indexer_pair[1]
          for indexer_pair in zip(indexers1, indexers2)
      ]
  
file_path: petastorm/petastorm/etl/rowgroup_indexing.py
imports: import logging
  import time
  from collections import namedtuple
  from pyarrow import parquet
  from six.moves import cPickle
  from six.moves import range
  from petastorm import utils
  from petastorm.etl import dataset_metadata
  from petastorm.etl.legacy import depickle_legacy_package_name_compatible
  from petastorm.fs_utils import FilesystemResolver
label_desc: Use image node_id 3 for calling a global function with example usage: _combine_indexers(indexers1, indexers2) and returns: unknown