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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_underscore(name):
 """ convert CamelCase style to under_score_case """

    as_list = []
    length = len(name)
    for index, i in enumerate(name):
        if index != 0 and index != length - 1 and i.isupper():
            as_list.append('_%s' % i.lower())
        else:
            as_list.append(i.lower())

    return ''.join(as_list)