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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 setup( cls, app_version: str, app_name: str, config_file_path: str, config_sep_str: str, root_path: typing.Optional[typing.List[str]] = None, ):
 """ Configures elib_config in one fell swoop :param app_version: version of the application :param app_name:name of the application :param config_file_path: path to the config file to use :param config_sep_str: separator for config values paths :param root_path: list of strings that will be pre-pended to *all* config values paths (useful to setup a prefix for the whole app) """

        cls.app_version = app_version
        cls.app_name = app_name
        cls.config_file_path = config_file_path
        cls.config_sep_str = config_sep_str
        cls.root_path = root_path