How to use the jiwer.transforms.ToLowerCase function in jiwer

################################################################################
# Implementation of the WER method, exposed publicly

_default_transform = tr.Compose(
    [
        tr.RemoveMultipleSpaces(),
        tr.Strip(),
        tr.SentencesToListOfWords(),
        tr.RemoveEmptyStrings(),
    ]
)

_standardize_transform = tr.Compose(
    [
        tr.ToLowerCase(),
        tr.ExpandCommonEnglishContractions(),
        tr.RemoveKaldiNonWords(),
        tr.RemoveWhiteSpace(replace_by_space=True),
    ]
)


def wer(
    truth: Union[str, List[str]],
    hypothesis: Union[str, List[str]],
    truth_transform: Union[tr.Compose, tr.AbstractTransform] = _default_transform,
    hypothesis_transform: Union[tr.Compose, tr.AbstractTransform] = _default_transform,
    **kwargs
) -> float:
    """
    Calculate the WER between between a set of ground-truth sentences and a set of