* Crie um arquivo `main.py` com:

```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">
<summary>Ou use <code>async def</code>...</summary>

* Kubernetes with an Ingress Controller like Nginx
    * With an external component like cert-manager for certificate renewals
* Handled internally by a cloud provider as part of their services (read below 👇)

### `scope`

🔌 💬 👈 👩‍💻 💪 📨 ➕1️⃣ 📨 🏑 "`scope`".

📨 🏑 📛 `scope` (⭐), ✋️ ⚫️ 🤙 📏 🎻 ⏮️ "↔" 🎏 🚀.

🔠 "↔" 🎻 (🍵 🚀).

👫 🛎 ⚙️ 📣 🎯 💂‍♂ ✔, 🖼:

* `users:read` ⚖️ `users:write` ⚠ 🖼.
* `instagram_basic` ⚙️ 👱📔 / 👱📔.
* `https://www.googleapis.com/auth/drive` ⚙️ 🇺🇸🔍.

!!! info
    Oauth2️⃣ "↔" 🎻 👈 📣 🎯 ✔ ✔.

    ⚫️ 🚫 🤔 🚥 ⚫️ ✔️ 🎏 🦹 💖 `:` ⚖️ 🚥 ⚫️ 📛.

                            * `security_scopes.scopes` 包含用于*路径操作*的 `["me", "items"]`
                            * `security_scopes.scopes` 包含*路径操作* `read_users_me` 的 `["me"]`，因为它在依赖项里被声明
                            * `security_scopes.scopes` 包含用于*路径操作* `read_system_status` 的 `[]`（空列表），并且它的依赖项 `get_current_user` 也没有声明任何 `scope`

!!! tip "提示"

    此处重要且**神奇**的事情是，`get_current_user` 检查每个*路径操作*时可以使用不同的 `scopes` 列表。

```mermaid
graph TB

query_extractor(["query_extractor"])
query_or_cookie_extractor(["query_or_cookie_extractor"])

read_query["/items/"]

query_extractor --> query_or_cookie_extractor --> read_query
```

## Using the same dependency multiple times

```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">
<summary>Və ya <code>async def</code>...</summary>

* Tạo một tệp tin `main.py` như sau:

```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">

    And it's possible that for your use case, the solution is in one of them.

## Read the Tutorial first

You could still use most of the features in **FastAPI** with the knowledge from the main [Tutorial - User Guide](../tutorial/index.md){.internal-link target=_blank}.

And the next sections assume you already read it, and assume that you know those main ideas.

## External Courses

* 함수에서 결과를 받아옵니다.
* *경로 작동 함수*에 있는 매개변수에 그 결과를 할당합니다

```mermaid
graph TB

common_parameters(["common_parameters"])
read_items["/items/"]
read_users["/users/"]

common_parameters --> read_items
common_parameters --> read_users
```

이렇게 하면 공용 코드를 한번만 적어도 되며, **FastAPI**는 *경로 작동*을 위해 이에 대한 호출을 처리합니다.

!!! check "확인"

```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">
<summary>Tàbí lò <code>async def</code>...</summary>