code: def _filter_columns(columns, spec):
      """Parse variable name from column label, removing element index, if any."""
      return [
          col
          for col in columns
          if col.split("[")[0].split(".")[0] in spec
      ]
  
imports: import logging
  import re
  from collections import defaultdict
  from copy import deepcopy
  from pathlib import Path
  import numpy
  from ..rcparams import rcParams
  from .base import dict_to_dataset, infer_stan_dtypes, make_attrs, requires
  from .inference_data import InferenceData
label_desc: Use image node_id 3 for calling a global function with example usage: _filter_columns(columns, spec) and returns: unknown