chore: import upstream snapshot with attribution

python/dgl/optim/__init__.py

@@ -0,0 +1,17 @@
+"""dgl optims."""
+import importlib
+import os
+import sys
+
+from ..backend import backend_name
+from ..utils import expand_as_pair
+
+
+def _load_backend(mod_name):
+    mod = importlib.import_module(".%s" % mod_name, __name__)
+    thismod = sys.modules[__name__]
+    for api, obj in mod.__dict__.items():
+        setattr(thismod, api, obj)
+
+
+_load_backend(backend_name)