sub: Optional[SubItem] = None
    model_config = {"json_schema_serialization_defaults_required": True}


class WithComputedField(BaseModel):
    name: str

    @computed_field
    @property
    def computed_field(self) -> str:
        return f"computed {self.name}"


def get_app_client(separate_input_output_schemas: bool = True) -> TestClient:
    app = FastAPI(separate_input_output_schemas=separate_input_output_schemas)

        # ModelField to its JSON Schema.
        return id(self)


def _has_computed_fields(field: ModelField) -> bool:
    computed_fields = field._type_adapter.core_schema.get("schema", {}).get(
        "computed_fields", []
    )
    return len(computed_fields) > 0


def get_schema_from_model_field(
    *,
    field: ModelField,
    model_name_map: ModelNameMap,
    field_mapping: dict[