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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 time_between_updates(self):
 """Time between current `last_updated` and previous `last_updated`"""

        if 'last_updated' not in self._original:
            return 0
        last_update = self._original['last_updated']
        this_update = self.last_updated
        return this_update - last_update