# Extra Pydantic data types
    "pydantic-extra-types >=2.0.0",
]

[project.scripts]
fastapi = "fastapi.cli:main"

[tool.pdm]
version = { source = "file", path = "fastapi/__init__.py" }
distribution = true

[tool.pdm.build]
source-includes = [
    "tests/",
    "docs_src/",
    "requirements*.txt",
    "scripts/",
    # For a test
    "docs/en/docs/img/favicon.png",

```
.
├── app
│   ├── __init__.py
│   ├── main.py
│   └── test_main.py
```

Файл `main.py`:

{* ../../docs_src/async_tests/app_a_py39/main.py *}

Файл `test_main.py` содержит тесты для `main.py`, теперь он может выглядеть так:

```
.
├── app
│   ├── __init__.py
│   ├── main.py
│   └── test_main.py
```

El archivo `main.py` tendría:

{* ../../docs_src/async_tests/app_a_py39/main.py *}

## Die Instanz parametrisieren { #parameterize-the-instance }

Und jetzt können wir `__init__` verwenden, um die Parameter der Instanz zu deklarieren, die wir zum „Parametrisieren“ der Abhängigkeit verwenden können:

{* ../../docs_src/dependencies/tutorial011_an_py39.py hl[9] *}

In diesem Fall wird **FastAPI** `__init__` nie berühren oder sich darum kümmern, wir werden es direkt in unserem Code verwenden.

或者

```Python
something(some_argument, some_keyword_argument="foo")
```

这就是 "可调用对象"。

## 类作为依赖项

您可能会注意到，要创建一个 Python 类的实例，您可以使用相同的语法。

举个例子:

```Python
class Cat:
    def __init__(self, name: str):
        self.name = name


fluffy = Cat(name="Mr Fluffy")
```

在这个例子中, `fluffy` 是一个 `Cat` 类的实例。

为了创建 `fluffy`，你调用了 `Cat` 。

所以，Python 类也是 **可调用对象**。

from typing import Annotated, Any

import pytest
from fastapi import Depends, FastAPI
from fastapi.responses import StreamingResponse
from fastapi.testclient import TestClient


class Session:
    def __init__(self) -> None:
        self.data = ["foo", "bar", "baz"]
        self.open = True

    def __iter__(self) -> Generator[str, None, None]:
        for item in self.data:
            if self.open:

  <span style="background-color:#009485"><font color="#D3D7CF"> FastAPI </font></span>  Starting production server 🚀

             Searching for package file structure from directories
             with <font color="#3465A4">__init__.py</font> files
             Importing from <font color="#75507B">/home/user/code/</font><font color="#AD7FA8">awesomeapp</font>

   <span style="background-color:#007166"><font color="#D3D7CF"> module </font></span>  🐍 main.py

code_block3_pattern = re.compile(r"^\s*```")
code_block4_pattern = re.compile(r"^\s*````")


class VisibleTextExtractor(HTMLParser):
    """Extract visible text from a string with HTML tags."""

    def __init__(self):
        super().__init__()
        self.text_parts = []

    def handle_data(self, data):
        self.text_parts.append(data)

    def extract_visible_text(self, html: str) -> str:
        self.reset()

```
.
├── app
│   ├── __init__.py
│   ├── main.py
│   └── test_main.py
```

The file `main.py` would have:

{* ../../docs_src/async_tests/app_a_py39/main.py *}

    """
    You shouldn't use this class directly.

    It's used internally to recognize when a default value has been overwritten, even
    if the overridden default value was truthy.
    """

    def __init__(self, value: Any):
        self.value = value

    def __bool__(self) -> bool:
        return bool(self.value)

    def __eq__(self, o: object) -> bool: