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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 clean_tmp_rootdir(self):
 """ clean up all used temporary rootdirs Returns ------- """

        for tmp_rootdir in list(self._dir_clean_list):
            rm_file_or_dir(tmp_rootdir)
            self._dir_clean_list.remove(tmp_rootdir)