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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 str2bool(string_, default='raise'):
 """ Convert a string to a bool. Parameters string_ : str default : {'raise', False} Default behaviour if none of the "true" strings is detected. Returns ------- boolean : bool Examples -------- True True False """

    true = ['true', 't', '1', 'y', 'yes', 'enabled', 'enable', 'on']
    false = ['false', 'f', '0', 'n', 'no', 'disabled', 'disable', 'off']
    if string_.lower() in true:
        return True
    elif string_.lower() in false or (not default):
        return False
    else:
        raise ValueError('The value \'{}\' cannot be mapped to boolean.'
                         .format(string_))