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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 _check_timestamp(self, timestamp):
 """Verify that timestamp is recentish."""

        timestamp = int(timestamp)
        now = int(time.time())
        lapsed = now - timestamp
        if lapsed > self.timestamp_threshold:
            raise Error('Expired timestamp: given %d and now %s has a '
                'greater difference than threshold %d' % (timestamp, now, 
                    self.timestamp_threshold))