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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 start(self, origin):
 """ Start this Tracer. Return a Python function suitable for use with sys.settrace(). """

        self.start_time = time.time()
        self.pause_until = None
        self.data.update(self._get_struct(origin, 'origin'))
        self.data_stack.append(self.data)
        sys.settrace(self._trace)
        return self._trace