# Body - 巢狀模型 { #body-nested-models }

使用 **FastAPI**，你可以定義、驗證、文件化，並使用任意深度的巢狀模型（感謝 Pydantic）。

## 列表欄位 { #list-fields }

你可以將屬性定義為某個子型別。例如，Python 的 `list`：

{* ../../docs_src/body_nested_models/tutorial001_py310.py hl[12] *}

這會讓 `tags` 成為一個列表，儘管尚未宣告列表元素的型別。

## 具有型別參數的列表欄位 { #list-fields-with-type-parameter }

不過，Python 有一種專門的方式來宣告具有內部型別（「型別參數」）的列表：

### 宣告帶有型別參數的 `list` { #declare-a-list-with-a-type-parameter }

                                    </la:info>
                                    <la:errors/>
                                </div>
                                    <%-- Form Fields --%>
                                <table class="table table-bordered" aria-label="<la:message key="labels.boost_document_rule_details" />">
                                    <tbody>
                                    <tr>

                                    </la:info>
                                    <la:errors/>
                                </div>
                                    <%-- Form Fields --%>
                                <table class="table table-bordered" aria-label="<la:message key="labels.related_query_details" />">
                                    <tbody>
                                    <tr>

| `terms_of_service` | `str` | APIの利用規約へのURLです。指定する場合、URLである必要があります。 |

                                    </la:info>
                                    <la:errors/>
                                </div>
                                    <%-- Form Fields --%>
                                <table class="table table-bordered" aria-label="<la:message key="labels.pathmap_details" />">
                                    <tbody>
                                    <tr>

        SMBUtil.writeInt4(contextStartOffsetFromHeader, base, offsetFieldPos);
        SMBUtil.writeInt4(ctx.length, base, offsetFieldPos + 4);

        // Assemble full body: base (fixed-size fields only), but actual context bytes sit elsewhere in the full packet
        // Return just the base; caller is responsible for placing ctx at the correct absolute offset.

labels: ["type=defect"]
body:
  - type: markdown
    attributes:
      value: >
        Thank you for filing a bug report. Please help us identify and resolve the bug by filling
        out the following fields. Before we begin, please make sure that the bug is still present in
        the [latest](https://github.com/google/guava/releases/latest) version of Guava available.

     * 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.

     */
    @ValidateTypeFailure
    public Long createdTime;

    /**
     * Initializes the form with default values for creation.
     * Sets the CRUD mode to CREATE and populates created by and created time fields
     * with current user and timestamp information.
     */
    public void initialize() {
        crudMode = CrudMode.CREATE;
        createdBy = ComponentUtil.getSystemHelper().getUsername();

            return buildDefaultQueryBuilder(fessConfig, context, (f, b) -> QueryBuilders.matchPhraseQuery(f, origQuery).boost(b));
        }

        context.addFieldLog(field, termRangeQuery.toString(field));
        final RangeQueryBuilder rangeQuery = QueryBuilders.rangeQuery(field);
        final BytesRef min = termRangeQuery.getLowerTerm();
        if (min != null) {
            if (termRangeQuery.includesLower()) {