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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 _update_callsafety(self, response):
 """ Update the callsafety data structure """

        if self.ratelimit is not None:
            self.callsafety['lastcalltime'] = time()
            self.callsafety['lastlimitremaining'] = int(response.headers.get('X-Rate-Limit-Remaining', 0))