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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(self):
 """Process the work unit, or wait for sentinel to exit"""

        while True:
            self.running = True
            workunit = self._workq.get()
            if is_sentinel(workunit):
                # Got sentinel
                break

            # Run the job / sequence
            workunit.process()
        self.running = False