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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 describe_snapshots(self, *snapshot_ids):
 """Describe available snapshots. TODO: ownerSet, restorableBySet """

        snapshot_set = {}
        for pos, snapshot_id in enumerate(snapshot_ids):
            snapshot_set["SnapshotId.%d" % (pos + 1)] = snapshot_id
        query = self.query_factory(
            action="DescribeSnapshots", creds=self.creds,
            endpoint=self.endpoint, other_params=snapshot_set)
        d = query.submit()
        return d.addCallback(self.parser.snapshots)