chore: import upstream snapshot with attribution

python/paddle/optimizer/__init__.py

@@ -0,0 +1,50 @@
+#   Copyright (c) 2020 PaddlePaddle Authors. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from . import lr  # noqa: F401
+from .adadelta import Adadelta
+from .adagrad import Adagrad
+from .adam import Adam
+from .adamax import Adamax
+from .adamw import AdamW
+from .asgd import ASGD
+from .lamb import Lamb
+from .lbfgs import LBFGS
+from .momentum import Momentum
+from .muon import Muon
+from .nadam import NAdam
+from .optimizer import Optimizer
+from .radam import RAdam
+from .rmsprop import RMSProp
+from .rprop import Rprop
+from .sgd import SGD
+
+__all__ = [
+    'Optimizer',
+    'Adagrad',
+    'Adam',
+    'AdamW',
+    'Adamax',
+    'ASGD',
+    'RAdam',
+    'RMSProp',
+    'Adadelta',
+    'SGD',
+    'Rprop',
+    'Momentum',
+    'NAdam',
+    'Lamb',
+    'LBFGS',
+    'Muon',
+]