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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 camel_to_under(name):
 """ Converts camel-case string to lowercase string separated by underscores. Written by epost (http://stackoverflow.com/questions/1175208). :param name: String to be converted :return: new String with camel-case converted to lowercase, underscored """

    s1 = re.sub("(.)([A-Z][a-z]+)", r"\1_\2", name)
    return re.sub("([a-z0-9])([A-Z])", r"\1_\2", s1).lower()