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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 make_snapshot_from_ops_hash( cls, record_root_hash, prev_consensus_hashes ):
 """ Generate the consensus hash from the hash over the current ops, and all previous required consensus hashes. """

        # mix into previous consensus hashes...
        all_hashes = prev_consensus_hashes[:] + [record_root_hash]
        all_hashes.sort()
        all_hashes_merkle_tree = MerkleTree( all_hashes )
        root_hash = all_hashes_merkle_tree.root()

        consensus_hash = StateEngine.calculate_consensus_hash( root_hash )
        return consensus_hash