code: def _compare_fn(
      preds: Union[str, List[str]], target: Union[str, List[str]]
  ):
      return cer(target, preds)
  
file_path: torchmetrics/tests/unittests/text/test_cer.py
imports: from typing import Callable, List, Union
  import pytest
  from torchmetrics.functional.text.cer import char_error_rate
  from torchmetrics.text.cer import CharErrorRate
  from torchmetrics.utilities.imports import _JIWER_AVAILABLE
  from unittests.text.helpers import TextTester
  from unittests.text.inputs import _inputs_error_rate_batch_size_1, _inputs_error_rate_batch_size_2
label_desc: Use image node_id 1 for calling a global function with example usage: _compare_fn(preds, target) and returns: cer