In those cases, you can use the *path operation decorator* parameter `response_model` instead of the return type.

You can use the `response_model` parameter in any of the *path operations*:

* `@app.get()`
* `@app.post()`
* `@app.put()`
* `@app.delete()`
* etc.

{* ../../docs_src/response_model/tutorial001_py310.py hl[17,22,24:27] *}

/// note

                final String webPackageKeyword = getWebPackageKeyword();
                if (!clazz.getName().contains(webPackageKeyword) ||
                // exclude app.web.api.admin packages
                        clazz.getName().contains(".app.web.api.admin.")) {
                    return;
                }
                check(srcFile, clazz, webPackageKeyword);
            }
        });
    }

 * either express or implied. See the License for the specific language
 * governing permissions and limitations under the License.
 */
package org.codelibs.fess.app.web.admin.dict.protwords;

import org.codelibs.fess.app.web.CrudMode;
import org.lastaflute.web.validation.Required;
import org.lastaflute.web.validation.theme.conversion.ValidateTypeFailure;

import jakarta.validation.constraints.Size;

/**

 */
package org.codelibs.fess.app.web.admin.searchlog;

import org.codelibs.fess.Constants;
import org.codelibs.fess.annotation.Secured;
import org.codelibs.fess.app.pager.SearchLogPager;
import org.codelibs.fess.app.service.SearchLogService;
import org.codelibs.fess.app.web.CrudMode;
import org.codelibs.fess.app.web.base.FessAdminAction;
import org.codelibs.fess.util.RenderDataUtil;

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
 * either express or implied. See the License for the specific language
 * governing permissions and limitations under the License.
 */
package org.codelibs.fess.app.web.admin.log;

import java.io.IOException;
import java.io.InputStream;
import java.nio.charset.StandardCharsets;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;

 * governing permissions and limitations under the License.
 */
package org.codelibs.fess.app.service;

import java.util.List;

import org.codelibs.core.beans.util.BeanUtil;
import org.codelibs.core.lang.StringUtil;
import org.codelibs.fess.Constants;
import org.codelibs.fess.app.pager.RelatedContentPager;
import org.codelibs.fess.mylasta.direction.FessConfig;

The first thing you should do is to "pin" the version of **FastAPI** you are using to the specific latest version that you know works correctly for your application.

For example, let's say you are using version `0.112.0` in your app.

If you use a `requirements.txt` file you could specify the version with:

```txt
fastapi[standard]==0.112.0
```

that would mean that you would use exactly the version `0.112.0`.

import org.codelibs.fess.annotation.Secured;
import org.codelibs.fess.app.pager.UserPager;
import org.codelibs.fess.app.service.GroupService;
import org.codelibs.fess.app.service.RoleService;
import org.codelibs.fess.app.service.UserService;
import org.codelibs.fess.app.web.CrudMode;
import org.codelibs.fess.app.web.base.FessAdminAction;
import org.codelibs.fess.app.web.base.login.FessLoginAssist;

from typing import Optional

app = FastAPI()


class Item(BaseModel):
    name: str
    price: float
    is_offer: bool = Optional[None]


@app.get("/")
def read_root():
    return {"Hello": "World"}


@app.get("/items/{item_id}")
def read_item(item_id: int, q: Optional[str] = None):
    return {"item_id": item_id, "q": q}


@app.put("/items/{item_id}")

### Erstellung

* Erstellen Sie eine Datei `main.py` mit:

```Python
from typing import Union

from fastapi import FastAPI

app = FastAPI()


@app.get("/")
def read_root():
    return {"Hello": "World"}


@app.get("/items/{item_id}")
def read_item(item_id: int, q: Union[str, None] = None):
    return {"item_id": item_id, "q": q}
```

<details markdown="1">