code: @Override
      public AssociativeArray2D copy() {
          AssociativeArray2D aArray2D = new AssociativeArray2D();
          for(Map.Entry<Object, AssociativeArray> entry: internalData.entrySet()) {
              aArray2D.internalData.put(entry.getKey(), entry.getValue().copy());
          }
          return aArray2D;
      }
docs: {@inheritDoc}