/**
   * Constructs a new entry array where each duplicated key from the original appears only once, at
   * its first position but with its final value. The {@code duplicates} map is modified.
   *
   * @param entries the original array of entries including duplicates
   * @param n the number of valid entries in {@code entries}
   * @param newN the expected number of entries once duplicates are removed

    // TODO(cpovirk): Consider using Object[] anyway.
    E[] array = (E[]) elements.toArray();
    /*
     * For a Set, we guess that it contains no duplicates. That's just a guess for purpose of
     * sizing; if the Set uses different equality semantics, it might contain duplicates according
     * to equals(), and we will deduplicate those properly, albeit at some cost in allocations.
     */
    int expectedSize =

            @Override
            public String[] getRoles(LdapUser user, String baseDn, String accountFilter, String groupFilter, Consumer<String[]> callback) {
                // Return roles with duplicates
                String[] roles = new String[] { "role1", "role2", "role1", "Uuser", "role2" };
                callback.accept(roles);
                return roles;
            }

            @Override

    assertEquals(
        "multiset.count(wrongType) didn't return 0", 0, getMultiset().count(WrongType.VALUE));
  }

  /**
   * Returns {@link Method} instances for the read tests that assume multisets support duplicates so
   * that the test of {@code Multisets.forSet()} can suppress them.
   */
  @J2ktIncompatible
  @GwtIncompatible // reflection
  public static List<Method> getCountDuplicateInitializingMethods() {

   * given collection in the order returned by the collection's iterator.
   *
   * @param collection the elements that the set should contain
   * @return a new {@code CompactLinkedHashSet} containing those elements (minus duplicates)
   */
  public static <E extends @Nullable Object> CompactLinkedHashSet<E> create(
      Collection<? extends E> collection) {
    CompactLinkedHashSet<E> set = createWithExpectedSize(collection.size());

* `frozenset`:
    * In requests and responses, treated the same as a `set`:
        * In requests, a list will be read, eliminating duplicates and converting it to a `set`.
        * In responses, the `set` will be converted to a `list`.
        * The generated schema will specify that the `set` values are unique (using JSON Schema's `uniqueItems`).
* `bytes`:

    // If there are no duplicate keys, hashTablePlus is the final hashTable value. If there *are*
    // duplicate keys, hashTablePlus consists of 3 elements: [0] the hashTable; [1] the number of
    // entries in alternatingKeysAndValues that are still valid after rewriting to remove
    // duplicates; [2] a Builder.DuplicateKey that records the first duplicate key we encountered

        return getSubjectGenerator().create(e0(), e1(), e1(), e2()).iterator();
      }
    }.test();
  }

  /**
   * Returns {@link Method} instances for the tests that assume multisets support duplicates so that
   * the test of {@code Multisets.forSet()} can suppress them.
   */
  @J2ktIncompatible
  @GwtIncompatible // reflection
  public static List<Method> getIteratorDuplicateInitializingMethods() {

      }
    }

    /**
     * Scans the first {@code size} elements of {@code entries} looking for duplicate keys. If
     * duplicates are found, a new correctly-sized array is returned with the same elements (up to
     * {@code size}), except containing only the last occurrence of each duplicate key. Otherwise
     * {@code null} is returned.
     */
    private static <K, V> Entry<K, V> @Nullable [] lastEntryForEachKey(

Then we can declare `tags` as a set of strings:

{* ../../docs_src/body_nested_models/tutorial003_py310.py hl[12] *}

With this, even if you receive a request with duplicate data, it will be converted to a set of unique items.

And whenever you output that data, even if the source had duplicates, it will be output as a set of unique items.

And it will be annotated / documented accordingly too.

## Nested Models { #nested-models }