Por exemplo, você pode usar isso para adicionar metadados para uma interface de usuário de front-end, etc.

///

## `Field` de argumentos adicionais

Ao usar `Field ()` com modelos Pydantic, você também pode declarar informações extras para o **JSON Schema** passando quaisquer outros argumentos arbitrários para a função.

  // Secret sauce for setting final fields; don't make it public.
  static final class FieldSetter<T> {
    private final Field field;

    private FieldSetter(Field field) {
      this.field = field;
      field.setAccessible(true);
    }

    void set(T instance, Object value) {
      try {
        field.set(instance, value);
      } catch (IllegalAccessException impossible) {
        throw new AssertionError(impossible);

        try {
            Field infoTypeField = Smb2SetInfoRequest.class.getDeclaredField("infoType");
            infoTypeField.setAccessible(true);
            byte actualInfoType = (byte) infoTypeField.get(request);
            assertEquals(Smb2Constants.SMB2_0_INFO_FILE, actualInfoType);

            Field fileInfoClassField = Smb2SetInfoRequest.class.getDeclaredField("fileInfoClass");

その追加情報はそのまま出力され、JSON Schemaに追加されます。

## `Field`の追加引数

後述する`Field`、`Path`、`Query`、`Body`などでは、任意の引数を関数に渡すことでJSON Schemaの追加情報を宣言することもできます:

{* ../../docs_src/schema_extra_example/tutorial002.py hl[4,10,11,12,13] *}

/// warning | 注意

これらの追加引数が渡されても、文書化のためのバリデーションは追加されず、注釈だけが追加されることを覚えておいてください。

///

## `Body`の追加引数

追加情報を`Field`に渡すのと同じように、`Path`、`Query`、`Body`などでも同じことができます。

        assertNotNull(result);

    }

    // Test with various field names
    public void test_convertFuzzyQuery_withVariousFields() {
        QueryContext context = new QueryContext("test", false);
        String[] fields = { "title", "content", "url", "site", "host", "mimetype" };

        for (String field : fields) {
            Term term = new Term(field, "fuzzy");
            FuzzyQuery fuzzyQuery = new FuzzyQuery(term);

     * This is a required field indicating when the job began.
     */
    @Required
    public String startTime;

    /**
     * The timestamp when the job completed execution.
     * This field indicates when the job finished, if it has completed.
     */
    public String endTime;

    /**
     * Initializes the form with default null values.

///

#### Data with values for fields with defaults { #data-with-values-for-fields-with-defaults }

But if your data has values for the model's fields with default values, like the item with ID `bar`:

```Python hl_lines="3  5"
{
    "name": "Bar",
    "description": "The bartenders",
    "price": 62,

    }

    /**
     * The unique identifier of the scheduler being edited.
     * This is a required field for identifying which scheduler to update.
     */
    @Required
    @Size(max = 1000)
    public String id;

    /**
     * The version number of the scheduler for optimistic locking.
     * This field is required to prevent concurrent modification conflicts

     */
    public String errorLog;

    /**
     * The number of times this URL has failed.
     * This is a required field that tracks repeated failures for the same URL.
     */
    @Required
    @ValidateTypeFailure
    public String errorCount;

    /**
     * The timestamp of the last access attempt for this URL.

  public static final String DATE = "Date";

  /** The HTTP {@code Pragma} header field name. */
  public static final String PRAGMA = "Pragma";

  /** The HTTP {@code Via} header field name. */
  public static final String VIA = "Via";

  /** The HTTP {@code Warning} header field name. */
  public static final String WARNING = "Warning";

  // HTTP Request header fields