```
.
├── app                  # "app" é um pacote Python
│   ├── __init__.py      # este arquivo torna "app" um "pacote Python"
│   ├── main.py          # "main" módulo, e.g. import app.main
│   ├── dependencies.py  # "dependencies" módulo, e.g. import app.dependencies
│   └── routers          # "routers" é um  "subpacote Python"
│   │   ├── __init__.py  # torna "routers" um "subpacote Python"

Aber eine Variable wie `user-agent` ist in Python nicht gültig.

Darum wird `Header` standardmäßig in Parameternamen den Unterstrich (`_`) zu einem Bindestrich (`-`) konvertieren.

HTTP-Header sind außerdem unabhängig von Groß-/Kleinschreibung, darum können Sie sie mittels der Standard-Python-Schreibweise deklarieren (auch bekannt als "snake_case").

</div>

////

### Lendo variáveis de ambiente com Python

Você também pode criar variáveis de ambiente fora do Python, no terminal (ou com qualquer outro método), e realizar a leitura delas no Python.

Por exemplo, você pode definir um arquivo `main.py` com o seguinte código:

```Python hl_lines="3"
import os

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

/// tip | Dica

        ```bash
        python -c "import pydantic; print(pydantic.version.VERSION)"
        ```
    validations:
      required: true
  - type: input
    id: python-version
    attributes:
      label: Python Version
      description: |
        What Python version are you using?

        You can find the Python version with:

        ```bash
        python --version

C:\Users\user\code\awesome-project\.venv\Scripts
```

そのため、ターミナルで `python` と入力した際に、OSはPythonプログラムを以下のパスで発見し、使用します。

```plaintext
C:\Users\user\code\awesome-project\.venv\Scripts\python
```

////

重要な点は、仮想環境のパスを `PATH` 変数の**先頭**に配置することです。OSは利用可能な他のPythonを見つけるより**前に**、この仮想環境のPythonを見つけるようになります。このようにして、 `python` を実行したときに、他の `python` （例えばグローバル環境の `python` ）ではなく、**その仮想環境の**Pythonを使用するようになります。

仮想環境を有効にして変更されることは他にもありますが、これが最も重要な変更のひとつです。

-   type: dropdown id: source attributes: label: Source description: Tensorflow

### Just Modern Python { #just-modern-python }

It's all based on standard **Python type** declarations (thanks to Pydantic). No new syntax to learn. Just standard modern Python.

If you need a 2 minute refresher of how to use Python types (even if you don't use FastAPI), check the short tutorial: [Python Types](python-types.md){.internal-link target=_blank}.

You write standard Python with types:

```Python

      - uses: actions/checkout@v5
      - name: Set up Python
        uses: actions/setup-python@v5
        with:
          python-version: "3.10"
      - name: Install build dependencies
        run: pip install build
      - name: Build source distribution
        env:
          TIANGOLO_BUILD_PACKAGE: ${{ matrix.package }}
        run: python -m build --sdist
      - name: Decompress source distribution
        run: |

/// info

Um hochgeladene Dateien und/oder Formulardaten zu empfangen, installieren Sie zuerst <a href="https://andrew-d.github.io/python-multipart/" class="external-link" target="_blank">`python-multipart`</a>.

Z. B. `pip install python-multipart`.

///

## `File` und `Form` importieren

{* ../../docs_src/request_forms_and_files/tutorial001_an_py39.py hl[3] *}

Обидві операції шляху вимагають заголовок `X-Token`.

//// tab | Python 3.10+

```Python
{!> ../../docs_src/app_testing/app_b_an_py310/main.py!}
```

////

//// tab | Python 3.9+

```Python
{!> ../../docs_src/app_testing/app_b_an_py39/main.py!}
```

////

//// tab | Python 3.8+

```Python
{!> ../../docs_src/app_testing/app_b_an/main.py!}
```

////