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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 get_snapshots(self):
 """ Returns a list of all completed snapshots for this volume ID. """

        ec2 = self.get_ec2_connection()
        rs = ec2.get_all_snapshots()
        all_vols = [self.volume_id] + self.past_volume_ids
        snaps = []
        for snapshot in rs:
            if snapshot.volume_id in all_vols:
                if snapshot.progress == '100%':
                    snapshot.date = boto.utils.parse_ts(snapshot.start_time)
                    snapshot.keep = True
                    snaps.append(snapshot)
        snaps.sort(cmp=lambda x,y: cmp(x.date, y.date))
        return snaps