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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 string_to_identifier(s, white_space_becomes='_'):
 """ Takes a string and makes it suitable for use as an identifier Translates to lower case Replaces white space by the white_space_becomes character (default=underscore). Removes and punctuation. """

    import re
    s = s.lower()
    s = re.sub(r"\s+", white_space_becomes, s) # replace whitespace with underscores
    s = re.sub(r"-", "_", s) # replace hyphens with underscores
    s = re.sub(r"[^A-Za-z0-9_]", "", s) # remove everything that's not a character, a digit or a _
    return s