idx.Option = index.Option
				}

				idx.Fields = append(idx.Fields, index.Fields...)
				sort.Slice(idx.Fields, func(i, j int) bool {
					return idx.Fields[i].priority < idx.Fields[j].priority
				})

				indexes[index.Name] = idx
			}
		}
	}
	for _, index := range indexes {
		if index.Class == "UNIQUE" && len(index.Fields) == 1 {
			index.Fields[0].Field.UniqueIndex = index.Name
		}
	}
	return indexes
}

# Body - Nested Models

With **FastAPI**, you can define, validate, document, and use arbitrarily deeply nested models (thanks to Pydantic).

## List fields

You can define an attribute to be a subtype. For example, a Python `list`:

=== "Python 3.10+"

    ```Python hl_lines="12"
    {!> ../../../docs_src/body_nested_models/tutorial001_py310.py!}
    ```

=== "Python 3.8+"

    ```Python hl_lines="14"

)

func TestNSQArgs_Validate(t *testing.T) {
	type fields struct {
		Enable      bool
		NSQDAddress xnet.Host
		Topic       string
		TLS         struct {
			Enable     bool
			SkipVerify bool
		}
	}
	tests := []struct {
		name    string
		fields  fields
		wantErr bool
	}{
		{
			name: "test1_missing_topic",
			fields: fields{
				Enable: true,
				NSQDAddress: xnet.Host{

    input.addListener(future, rejectionPropagatingExecutor(executor, future));
    return future;
  }

  /*
   * In certain circumstances, this field might theoretically not be visible to an afterDone() call
   * triggered by cancel(). For details, see the comments on the fields of TimeoutFuture.
   */
  @CheckForNull @LazyInit ListenableFuture<? extends V> inputFuture;
  @CheckForNull @LazyInit Class<X> exceptionType;

// GetIdentityFieldValuesMapFromValues get identity map from fields
func GetIdentityFieldValuesMapFromValues(ctx context.Context, values []interface{}, fields []*Field) (map[string][]reflect.Value, [][]interface{}) {
	resultsMap := map[string][]reflect.Value{}
	results := [][]interface{}{}

	for _, v := range values {
		rm, rs := GetIdentityFieldValuesMap(ctx, reflect.Indirect(reflect.ValueOf(v)), fields)
		for k, v := range rm {

	test1ActiveBuckets2[BucketOptions{Name: "bucket", ReplicationARN: "arn"}] = m1MiBPS

	tests := []struct {
		name   string
		fields fields
		want   *BucketBandwidthReport
		want2  *BucketBandwidthReport
	}{
		{
			name: "ZeroToOne",
			fields: fields{
				activeBuckets: test1ActiveBuckets,
				endTime:       start.Add(1 * time.Second),
				update2:       oneMiB,

        return getUpdatedAt();
    }

    public void addField(final String key, final Object value) {
        fields.put(key, value);
    }

    @Override
    public Map<String, Object> toSource() {
        final Map<String, Object> sourceMap = super.toSource();
        if (fields != null) {
            sourceMap.putAll(fields);
        }
        return sourceMap;
    }

    @Override

        if (value instanceof final LocalDateTime ldt) {
            final ZonedDateTime zdt = ZonedDateTime.of(ldt, ZoneId.systemDefault());
            super.addFieldToSource(sourceMap, field, DateTimeFormatter.ISO_INSTANT.format(zdt));
        } else {
            super.addFieldToSource(sourceMap, field, value);
        }
    }

    @Override

                : ComponentUtil.getRoleQueryHelper().build(searchRequestType).stream().filter(StringUtil::isNotBlank)
                        .toArray(n -> new String[n]);
        final String[] baseFields = fields != null ? fields : fessConfig.getSuggestPopularWordFieldsAsArray();
        final String[] baseExcludes = excludes != null ? excludes : fessConfig.getSuggestPopularWordExcludesAsArray();
        try {

    ```

For example, in one of the ways the OAuth2 specification can be used (called "password flow") it is required to send a `username` and `password` as form fields.

The <abbr title="specification">spec</abbr> requires the fields to be exactly named `username` and `password`, and to be sent as form fields, not JSON.