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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 _get_regex_pattern(label):
 """Return a regular expression of the label. This takes care of plural and different kinds of separators. """

    parts = _split_by_punctuation.split(label)

    for index, part in enumerate(parts):
        if index % 2 == 0:
            # Word
            if not parts[index].isdigit() and len(parts[index]) > 1:
                parts[index] = _convert_word(parts[index])
        else:
            # Punctuation
            if not parts[index + 1]:
                # The separator is not followed by another word. Treat
                # it as a symbol.
                parts[index] = _convert_punctuation(
                    parts[index],
                    current_app.config["CLASSIFIER_SYMBOLS"]
                )
            else:
                parts[index] = _convert_punctuation(
                    parts[index],
                    current_app.config["CLASSIFIER_SEPARATORS"]
                )

    return "".join(parts)