code: public void setHelperWorkspace(@NonNull String key, Pointer value){
          if(helperWorkspacePointers == null){
              helperWorkspacePointers = new HashMap<>();
          }
          helperWorkspacePointers.put(key, value);
      }
docs: Set the pointer to the helper memory. Usually used for CuDNN workspace memory sharing.
  NOTE: Don't use this method unless you are fully aware of how it is used to manage CuDNN memory!
  Will (by design) throw a NPE if the underlying map (set from MultiLayerNetwork or ComputationGraph) is not set.
  
  @param key   Key for the helper workspace pointer
  @param value Pointer