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doc/changes/DM-46776.feature.rst

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+* Added ``Butler.retrieve_artifacts_zip`` and ``QuantumBackedButler.retrieve_artifacts_zip`` methods to retrieve the dataset artifacts and store them into a zip file.
+* Added ``Butler.ingest_zip`` to ingest the contents of a Zip file.
+* Added ``SerializedDatasetRefContainerV1`` class to allow a collection of ``DatasetRef`` to be serialized efficiently.
+  JSON serializations made using this class will be supported.
+* Added ``--zip`` parameter to ``butler retrieve-artifacts``.
+* Changed ``Butler.retrieveArtifacts`` to always write a JSON index file describing where the artifacts came from.
+* Added a ``butler ingest-zip`` command-line tool for ingesting zip files created by ``butler retrieve-artifacts``.