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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 process(self, job):
        '''Process a job'''
        sandbox = self.sandboxes.pop(0)
        try:
            with Worker.sandbox(sandbox):
                job.sandbox = sandbox
                job.process()
        finally:
            # Delete its entry from our greenlets mapping
            self.greenlets.pop(job.jid, None)
            self.sandboxes.append(sandbox)