Merge pull request #10331 from arrybn:python_dnn_net

diff --cc modules/dnn/include/opencv2/dnn/dnn.hpp
index 3ded147,a0eca0a..7488351
--- 1/modules/dnn/include/opencv2/dnn/dnn.hpp
--- 2/modules/dnn/include/opencv2/dnn/dnn.hpp
+++ b/modules/dnn/include/opencv2/dnn/dnn.hpp
@@@ -423,9 -423,18 +423,9 @@@ CV__DNN_EXPERIMENTAL_NS_BEGI
           *  @param outputBlobs contains all output blobs for each layer specified in @p outBlobNames.
           *  @param outBlobNames names for layers which outputs are needed to get
           */
-         void forward(std::vector<std::vector<Mat> >& outputBlobs,
-                      const std::vector<String>& outBlobNames);
+         CV_WRAP_AS(forwardAndRetrieve) void forward(CV_OUT std::vector<std::vector<Mat> >& outputBlobs,
+                                                     const std::vector<String>& outBlobNames);
  
 -        //TODO:
 -        /** @brief Optimized forward.
 -         *  @warning Not implemented yet.
 -         *  @details Makes forward only those layers which weren't changed after previous forward().
 -         */
 -        void forwardOpt(LayerId toLayer);
 -        /** @overload */
 -        void forwardOpt(const std::vector<LayerId> &toLayers);
 -
          /**
           * @brief Compile Halide layers.
           * @param[in] scheduler Path to YAML file with scheduling directives.