* @param newN the expected number of entries once duplicates are removed
   * @param duplicates a map of canonical {@link Entry} objects for each duplicate key. This map
   *     will be updated by the method, setting each value to false as soon as the {@link Entry} has
   *     been included in the new entry array.
   * @return an array of {@code newN} entries where no key appears more than once.
   */