src/transformers/models/whisper/english_normalizer.py/EnglishTextNormalizer/__call__
class EnglishTextNormalizer:    def __call__(self, s: str):
        s = s.lower()

        s = re.sub(r"[<\[][^>\]]*[>\]]", "", s)  # remove words between brackets
        s = re.sub(r"\(([^)]+?)\)", "", s)  # remove words between parenthesis
        s = re.sub(self.ignore_patterns, "", s)
        s = re.sub(r"\s+'", "'", s)  # standardize when there's a space before an apostrophe

        for pattern, replacement in self.replacers.items():
            s = re.sub(pattern, replacement, s)

        s = re.sub(r"(\d),(\d)", r"\1\2", s)  # remove commas between digits
        s = re.sub(r"\.([^0-9]|$)", r" \1", s)  # remove periods not followed by numbers
        s = remove_symbols_and_diacritics(s, keep=".%$¢€£")  # keep some symbols for numerics

        s = self.standardize_numbers(s)
        s = self.standardize_spellings(s)

        # now remove prefix/suffix symbols that are not preceded/followed by numbers
        s = re.sub(r"[.$¢€£]([^0-9])", r" \1", s)
        s = re.sub(r"([^0-9])%", r"\1 ", s)

        s = re.sub(r"\s+", " ", s)  # replace any successive whitespace characters with a space

        return s