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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 run_once(self):
        '''comsume queues and feed tasks to fetcher, once'''

        self._update_projects()
        self._check_task_done()
        self._check_request()
        while self._check_cronjob():
            pass
        self._check_select()
        self._check_delete()
        self._try_dump_cnt()