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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def conformPadding(cls, chars):
 """ Ensure alternate input padding formats are conformed to formats defined in PAD_MAP If chars is already a format defined in PAD_MAP, then it is returned unmodified. Example:: '#' -> '#' '@@@@' -> '@@@@' '%04d' -> '#' Args: chars (str):
 input padding chars Returns: str: conformed padding chars Raises: ValueError: If chars contains invalid padding characters """

        pad = chars
        if pad and pad[0] not in PAD_MAP:
            pad = cls.getPaddingChars(cls.getPaddingNum(pad))
        return pad