```

    </div>

!!! note
    The command `uvicorn main:app` refers to:

    * `main`: the file `main.py` (the Python "module").
    * `app`: the object created inside of `main.py` with the line `app = FastAPI()`.

    It is equivalent to:

    ```Python
    from main import app
    ```

!!! warning

classes in it, e.g. in a `List[Item]`), the Pydantic model class(es) will be a different one (the "cloned" one). So, an object that is a subclass won't simply pass the validation and returned as-is, because it is no longer a sub-class of the cloned `response_model`. Instead, a new Pydantic model object will be created with the contents of the returned object. So, it will be a new object (made with the data from the returned one), and will be filtered by the cloned `response_model`, containing only the...

Including external libraries also based on Pydantic, as <abbr title="Object-Relational Mapper">ORM</abbr>s, <abbr title="Object-Document Mapper">ODM</abbr>s for databases.

This also means that in many cases you can pass the same object you get from a request **directly to the database**, as everything is validated automatically.

The same applies the other way around, in many cases you can just pass the object you get from the database **directly to the client**.

```Python hl_lines="9-13  36-53"
{!../../../docs_src/openapi_webhooks/tutorial001.py!}
```

The webhooks that you define will end up in the **OpenAPI** schema and the automatic **docs UI**.

!!! info
    The `app.webhooks` object is actually just an `APIRouter`, the same type you would use when structuring your app with multiple files.

    * Kiểm tra xem nó có một thuộc tính tùy chọn là `is_offer` không? Nếu có, nó phải có kiểu `bool`.
    * Tất cả những kiểm tra này cũng được áp dụng với các JSON lồng nhau.
* Chuyển đổi tự động các JSON object đến và JSON object đi.
* Tài liệu hóa mọi thứ với OpenAPI, tài liệu đó có thể được sử dụng bởi:

    * Các hệ thống tài liệu có thể tương tác.
    * Hệ thống sinh code tự động, cho nhiều ngôn ngữ lập trình.

</div>

<details markdown="1">
<summary>Nipa aṣẹ kóòdù náà <code>uvicorn main:app --reload</code>...</summary>

Àṣẹ `uvicorn main:app` ń tọ́ka sí:

* `main`: fáìlì náà 'main.py' (Python "module").
* `app` jẹ object( i.e. nǹkan) tí a ṣẹ̀dá nínú `main.py` pẹ̀lú ilà `app = FastAPI()`.
* `--reload`: èyí yóò jẹ́ ki olupin tún bẹ̀rẹ̀ lẹ́hìn àwọn àyípadà kóòdù. Jọ̀wọ́, ṣe èyí fún ìdàgbàsókè kóòdù nìkan, má ṣe é ṣe lori àgbéjáde kóòdù tabi fún iṣelọpọ kóòdù.

Then it would be very easy to provide a different settings object during testing by creating a dependency override for `get_settings`:

```Python hl_lines="9-10  13  21"
{!../../../docs_src/settings/app02/test_main.py!}
```

In the dependency override we set a new value for the `admin_email` when creating the new `Settings` object, and then we return that new object.

Then we can test that it is used.

    the key value sent in the query parameter automatically and provides it as the
    dependency result. But it doesn't define how to send that API key to the client.

    ## Usage

    Create an instance object and use that object as the dependency in `Depends()`.

    The dependency result will be a string containing the key value.

    ## Example

    ```python
    from fastapi import Depends, FastAPI

```

</div>

<details markdown="1">
<summary><code>uvicorn main:app --reload</code> 명령에 관하여...</summary>

명령 `uvicorn main:app`은 다음을 나타냅니다:

* `main`: `main.py` 파일 (파이썬 "모듈").
* `app`: the object created inside of `main.py` with the line `app = FastAPI()`.
* `--reload`: 코드가 변경된 후 서버 재시작하기. 개발환경에서만 사용하십시오.

</details>

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