code: def calc_loss_function_change(
      model_file, pool_path, pairs, cd_path, fstr_path, args=None
  ):
      cmd = (
          get_catboost_binary_path(),
          "fstr",
          "-m",
          model_file,
          "--input-path",
          pool_path,
          "--output-path",
          fstr_path,
          "--fstr-type",
          "LossFunctionChange",
      )
      if pairs:
          cmd += ("--input-pairs", pairs)
      if cd_path:
          cmd += ("--column-description", cd_path)
      if args:
          cmd += tuple(args.strip().split())
      yatest.common.execute(cmd)
  
imports: import os
  import pytest
  import re
  import sys
  import tempfile
  import time
  from .common_helpers import *
  import zipfile
  from testpath.tempdir import TemporaryDirectory
  import yatest.common.network
label_desc: Use image node_id 8 for calling a global function with example usage: calc_loss_function_change(model_file, pool_path, pairs, cd_path, fstr_path, args) without return types