code: @Nonnull
      public DeploymentNode addDeploymentNode(@Nonnull String name, @Nullable String description, @Nullable String technology) {
          return addDeploymentNode(DeploymentElement.DEFAULT_DEPLOYMENT_ENVIRONMENT, name, description, technology);
      }
docs: Adds a top-level deployment node to this model.
  
  @param name        the name of the deployment node
  @param description the description of the deployment node
  @param technology  the technology associated with the deployment node
  @return a DeploymentNode instance
  @throws IllegalArgumentException if the name is not specified, or a top-level deployment node with the same name already exists in the model