builder.field(SESSION_ID, sessionId);
        }
        if (method != null) {
            builder.field(METHOD, method);
        }
        if (url != null) {
            builder.field(URL, url);
        }
        if (parentUrl != null) {
            builder.field(PARENT_URL, parentUrl);
        }
        if (depth != null) {
            builder.field(DEPTH, depth);
        }

        /**
         * Splits a field name into its components.
         *
         * @param defaultField the default field name
         * @param field the field name to split
         * @return a Pair containing the field name and extension key
         */
        protected Pair<String, String> splitField(final String defaultField, final String field) {
            final int indexOf = field.indexOf(':');
            if (indexOf < 0) {

        }
    }

    // Helper method to set private dialectIndex field using reflection
    private void setDialectIndex(SmbComNegotiateResponse response, int dialectIndex) {
        try {
            Field field = response.getClass().getDeclaredField("dialectIndex");
            field.setAccessible(true);
            field.set(response, dialectIndex);
        } catch (Exception e) {

        // Verify that the 'recordName' field in the superclass (NameServicePacket) is initialized
        Field recordNameField = NameServicePacket.class.getDeclaredField("recordName");
        recordNameField.setAccessible(true); // Allow access to protected field
        Name recordName = (Name) recordNameField.get(nameQueryResponse);

    from fastapi._compat import v2

    field_info = FieldInfo(annotation=list[str] | None)
    field = v2.ModelField(name="items", field_info=field_info)
    result = v2.serialize_sequence_value(field=field, value=["a", "b", "c"])
    assert result == ["a", "b", "c"]
    assert isinstance(result, list)


def test_serialize_sequence_value_with_optional_list_pipe_union():

## 匯入 `Field` { #import-field }

首先，你需要匯入它：

{* ../../docs_src/body_fields/tutorial001_an_py310.py hl[4] *}


/// warning

請注意，`Field` 是直接從 `pydantic` 匯入的，不像其他（如 `Query`、`Path`、`Body` 等）是從 `fastapi` 匯入。

///

## 宣告模型屬性 { #declare-model-attributes }

接著你可以在模型屬性上使用 `Field`：

        existingList.add("existing");
        fieldLogMap.put("field", existingList);
        getMockRequest().setAttribute(Constants.FIELD_LOGS, fieldLogMap);

        queryContext = new QueryContext("test", true);
        queryContext.addFieldLog("field", "new");

        List<String> list = fieldLogMap.get("field");
        assertEquals(2, list.size());
        assertEquals("existing", list.get(0));

    /**
     * Set a field with the specified date. If the field is not found, it is added. If the field is
     * found, the existing values are replaced.
     */
    operator fun set(
      name: String,
      value: Date,
    ) = set(name, value.toHttpDateString())

    /**
     * Set a field with the specified instant. If the field is not found, it is added. If the field

    /**
     * Gets the location of the specified field in the input
     * source.
     *
     * @param field The key of the field, must not be
     * <code>null</code>.
     * @return The location of the field in the input source or
     * <code>null</code> if unknown.
     */
    public InputLocation getLocation(Object field);
    /**
     * Sets the location of the specified field.
     *

# ボディ - フィールド { #body-fields }

`Query`や`Path`、`Body`を使って *path operation関数* のパラメータに追加のバリデーションやメタデータを宣言するのと同じように、Pydanticの`Field`を使ってPydanticモデルの内部でバリデーションやメタデータを宣言することができます。

## `Field`のインポート { #import-field }

まず、以下のようにインポートします:

{* ../../docs_src/body_fields/tutorial001_an_py310.py hl[4] *}


/// warning | 注意

`Field`は他の全てのもの（`Query`、`Path`、`Body`など）とは違い、`fastapi`からではなく、`pydantic`から直接インポートされていることに注意してください。

///