code: public static <E extends Comparable> TreeSet<E> newTreeSet(Iterable<? extends E> elements) {
      TreeSet<E> set = newTreeSet();
      Iterables.addAll(set, elements);
      return set;
    }
docs: Creates a <i>mutable</i> {@code TreeSet} instance containing the given elements sorted by their
  natural ordering.
  
  <p><b>Note:</b> if mutability is not required, use {@link ImmutableSortedSet#copyOf(Iterable)}
  instead.
  
  <p><b>Note:</b> If {@code elements} is a {@code SortedSet} with an explicit comparator, this
  method has different behavior than {@link TreeSet#TreeSet(SortedSet)}, which returns a {@code
  TreeSet} with that comparator.
  
  <p><b>Note for Java 7 and later:</b> this method is now unnecessary and should be treated as
  deprecated. Instead, use the {@code TreeSet} constructor directly, taking advantage of the new
  <a href="http://goo.gl/iz2Wi">"diamond" syntax</a>.
  
  <p>This method is just a small convenience for creating an empty set and then calling {@link
  Iterables#addAll}. This method is not very useful and will likely be deprecated in the future.
  
  @param elements the elements that the set should contain
  @return a new {@code TreeSet} containing those elements (minus duplicates)