```Python hl_lines="2-5  15  21"
{!../../../docs_src/handling_errors/tutorial006.py!}
```

デフォルトの例外ハンドラを`fastapi.exception_handlers`からインポートして再利用することができます:

```Python hl_lines="2 3 4 5 15 21"
{!../../../docs_src/handling_errors/tutorial006.py!}
```

この例では、非常に表現力のあるメッセージでエラーを`print`しています。

```Python
with open("./somefile.txt") as f:
    contents = f.read()
    print(contents)
```

🔘, `open("./somefile.txt")` ✍ 🎚 👈 🤙 "🔑 👨‍💼".

🕐❔ `with` 🍫 🏁, ⚫️ ⚒ 💭 🔐 📁, 🚥 📤 ⚠.

🕐❔ 👆 ✍ 🔗 ⏮️ `yield`, **FastAPI** 🔜 🔘 🗜 ⚫️ 🔑 👨‍💼, & 🌀 ⚫️ ⏮️ 🎏 🔗 🧰.

    </div>

### ✍ 🇨🇻 {🐍

👆 💪 ✍ 🌐 🔢 🏞 🐍, 📶 (⚖️ ⏮️ 🙆 🎏 👩‍🔬), &amp; ⤴️ ✍ 👫 🐍.

🖼 👆 💪 ✔️ 📁 `main.py` ⏮️:

```Python hl_lines="3"
import os

name = os.getenv("MY_NAME", "World")
print(f"Hello {name} from Python")
```

!!! tip
    🥈 ❌ <a href="https://docs.python.org/3.8/library/os.html#os.getenv" class="external-link" target="_blank">`os.getenv()`</a> 🔢 💲 📨.

```Python
user_dict = user_in.dict()
```

то теперь у нас есть `dict` с данными модели в переменной `user_dict` (это `dict` вместо объекта Pydantic-модели).

И если мы вызовем:

```Python
print(user_dict)
```

мы можем получить `dict` с такими данными:

```Python
{
    'username': 'john',
    'password': 'secret',
    'email': '******@****.***',
    'full_name': None,
}
```

I have been avoiding the creation of a new framework for several years. First I tried to solve all the features covered by **FastAPI** using many different frameworks, plug-ins, and tools.

!!! check
    So, with the same Python type declaration, **FastAPI** gives you data validation.

    Notice that the error also clearly states exactly the point where the validation didn't pass.

    This is incredibly helpful while developing and debugging code that interacts with your API.

## Documentation

and then we call:

```Python
user_dict = user_in.dict()
```

we now have a `dict` with the data in the variable `user_dict` (it's a `dict` instead of a Pydantic model object).

And if we call:

```Python
print(user_dict)
```

we would get a Python `dict` with:

```Python
{
    'username': 'john',
    'password': 'secret',
    'email': '******@****.***',
    'full_name': None,
}
```

!!! check "vérifier"
    Donc, avec ces mêmes déclarations de type Python, **FastAPI** vous fournit de la validation de données.

    Notez que l'erreur mentionne le point exact où la validation n'a pas réussi.

    Ce qui est incroyablement utile au moment de développer et débugger du code qui interagit avec votre API.

## Documentation

```Python hl_lines="3"
{!../../../docs_src/first_steps/tutorial001.py!}
```

Here the `app` variable will be an "instance" of the class `FastAPI`.

This will be the main point of interaction to create all your API.

### Step 3: create a *path operation*

#### Path

"Path" here refers to the last part of the URL starting from the first `/`.

So, in a URL like:

```