chore: import upstream snapshot with attribution

decoding/GAD/train.py

@@ -0,0 +1,14 @@
+#!/usr/bin/env python3 -u
+# Copyright (c) Facebook, Inc. and its affiliates.
+#
+# This source code is licensed under the MIT license found in the
+# LICENSE file in the root directory of this source tree.
+"""
+Legacy entry point. Use fairseq_cli/train.py or fairseq-train instead.
+"""
+
+from fairseq_cli.train import cli_main
+
+
+if __name__ == "__main__":
+    cli_main()