code: public Iterable<BoxTaskAssignment.Info> getAllAssignments(String ... fields) {
          final QueryStringBuilder builder = new QueryStringBuilder();
          if (fields.length > 0) {
              builder.appendParam("fields", fields);
          }
          return new Iterable<BoxTaskAssignment.Info>() {
              public Iterator<BoxTaskAssignment.Info> iterator() {
                  URL url = GET_ASSIGNMENTS_URL_TEMPLATE.buildWithQuery(
                          BoxTask.this.getAPI().getBaseURL(), builder.toString(), BoxTask.this.getID());
                  return new BoxTaskAssignmentIterator(BoxTask.this.getAPI(), url);
              }
          };
      }
docs: Gets an iterable of all the assignments of this task.
  @param fields the fields to retrieve.
  @return     an iterable containing info about all the assignments.