code: public static <E extends Comparable> TreeMultiset<E> create(Iterable<? extends E> elements) {
      TreeMultiset<E> multiset = create();
      Iterables.addAll(multiset, elements);
      return multiset;
    }
docs: Creates an empty multiset containing the given initial elements, sorted according to the
  elements' natural order.
  
  <p>This implementation is highly efficient when {@code elements} is itself a {@link Multiset}.
  
  <p>The type specification is {@code <E extends Comparable>}, instead of the more specific
  {@code <E extends Comparable<? super E>>}, to support classes defined without generics.