code: public Datatype.Builder addGeneratedBuilderAnnotations(Excerpt element) {
      if (generatedBuilderAnnotations instanceof ImmutableList) {
        generatedBuilderAnnotations = new ArrayList<>(generatedBuilderAnnotations);
      }
      generatedBuilderAnnotations.add(Objects.requireNonNull(element));
      return (Datatype.Builder) this;
    }
docs: Adds {@code element} to the list to be returned from {@link
  Datatype#getGeneratedBuilderAnnotations()}.
  
  @return this {@code Builder} object
  @throws NullPointerException if {@code element} is null