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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_dirs(self):
 """ Remove temporary dir associated with this backend instance. :return: None """


        def onerror(fnc, path, excinfo):
            # we might not have rights to do this, the files could be owned by root
            self.logger.info("we were not able to remove temporary file %s: %s", path, excinfo[1])

        shutil.rmtree(self.tmpdir, onerror=onerror)
        self.tmpdir = None
        global _backend_tmpdir
        _backend_tmpdir = None