Added support for the MxNet op take (#4071)

docs/MO_DG/prepare_model/Supported_Frameworks_Layers.md

@@ -108,6 +108,7 @@ Standard MXNet\* symbols:
 | SoftmaxActivation | No |
 | SoftmaxOutput | No |
 | SoftSign | No |
+| Take | The attribute 'mode' is not supported |
 | Tile | No |
 | UpSampling | No |
 | Where | No |

model-optimizer/automation/package_BOM.txt

@@ -224,6 +224,7 @@ extensions/front/mxnet/ssd_pattern_remove_transpose.py
 extensions/front/mxnet/ssd_reorder_detection_out_inputs.py
 extensions/front/mxnet/stack_ext.py
 extensions/front/mxnet/swapaxis_ext.py
+extensions/front/mxnet/take_ext.py
 extensions/front/mxnet/tile_ext.py
 extensions/front/mxnet/tile_replacer.py
 extensions/front/mxnet/transpose_ext.py

model-optimizer/extensions/front/mxnet/take_ext.py

@@ -0,0 +1,33 @@
+"""
+ Copyright (C) 2017-2021 Intel Corporation
+
+ 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 extensions.ops.gather import AttributedGather
+from mo.front.extractor import FrontExtractorOp
+from mo.front.mxnet.extractors.utils import get_mxnet_layer_attrs
+from mo.graph.graph import Node
+
+
+class TakeExtractor(FrontExtractorOp):
+    op = 'take'
+    enabled = True
+
+    @classmethod
+    def extract(cls, node: Node):
+        attrs = get_mxnet_layer_attrs(node.symbol_dict)
+        AttributedGather.update_node_stat(node, {
+            'axis': attrs.int('axis', 0),
+        })
+        return cls.enabled