contrib = _LazyLoader("contrib", globals(), "tensorflow.contrib",
                      _CONTRIB_WARNING)
# The templated code that replaces the placeholder above sometimes
# sets the __all__ variable. If it does, we have to be sure to add
# "contrib".
if "__all__" in vars():
  vars()["__all__"].append("contrib")

from tensorflow.python.platform import flags
# The "app" module will be imported as part of the placeholder section above.

		}
	} else if arr, ok := value.ToArray(); ok {
		v = arr
	} else {
		return nil, fmt.Errorf("unsupported sql value %v and type %v", value, value.GetTypeString())
	}

	name = strings.ReplaceAll(name, "*", "__ALL__")
	r.KVS = append(r.KVS, jstream.KV{Key: name, Value: v})
	return r, nil
}

// WriteCSV - encodes to CSV data.
func (r *Record) WriteCSV(writer io.Writer, opts sql.WriteCSVOpts) error {
	var csvRecord []string

try:
  del python
except NameError:
  pass
try:
  del core
except NameError:
  pass
try:
  del compiler
except NameError:
  pass

✋️ 👥 💚 💪 🔗 👈 🔧 🎚.

##  "🇧🇲" 👐

🐍 📤 🌌 ⚒ 👐 🎓 "🇧🇲".

🚫 🎓 ⚫️ (❔ ⏪ 🇧🇲), ✋️ 👐 👈 🎓.

👈, 👥 📣 👩‍🔬 `__call__`:

```Python hl_lines="10"
{!../../docs_src/dependencies/tutorial011.py!}
```

👉 💼, 👉 `__call__` ⚫️❔ **FastAPI** 🔜 ⚙️ ✅ 🌖 🔢 & 🎧-🔗, & 👉 ⚫️❔ 🔜 🤙 🚶‍♀️ 💲 🔢 👆 *➡ 🛠️ 🔢* ⏪.

## 🔗 👐

& 🔜, 👥 💪 ⚙️ `__init__` 📣 🔢 👐 👈 👥 💪 ⚙️ "🔗" 🔗:

class CallableDependency:
    def __call__(self, value: str) -> str:
        return value


class CallableGenDependency:
    def __call__(self, value: str) -> Generator[str, None, None]:
        yield value


class AsyncCallableDependency:
    async def __call__(self, value: str) -> str:
        return value


class AsyncCallableGenDependency:
    async def __call__(self, value: str) -> AsyncGenerator[str, None]:

Not the class itself (which is already a callable), but an instance of that class.

To do that, we declare a method `__call__`:

{* ../../docs_src/dependencies/tutorial011_an_py39.py hl[12] *}

from typing import Annotated

from fastapi import Depends, FastAPI

app = FastAPI()


class FixedContentQueryChecker:
    def __init__(self, fixed_content: str):
        self.fixed_content = fixed_content

    def __call__(self, q: str = ""):
        if q:
            return self.fixed_content in q
        return False


checker = FixedContentQueryChecker("bar")


@app.get("/query-checker/")

from typing_extensions import Annotated

app = FastAPI()


class FixedContentQueryChecker:
    def __init__(self, fixed_content: str):
        self.fixed_content = fixed_content

    def __call__(self, q: str = ""):
        if q:
            return self.fixed_content in q
        return False


checker = FixedContentQueryChecker("bar")


@app.get("/query-checker/")

Em Python existe uma maneira de fazer com que uma instância de uma classe seja um "chamável".

Não propriamente a classe (que já é um chamável), mas a instância desta classe.

Para fazer isso, nós declaramos o método `__call__`:

//// tab | Python 3.9+

```Python hl_lines="12"
{!> ../../docs_src/dependencies/tutorial011_an_py39.py!}
```

////

//// tab | Python 3.8+

```Python hl_lines="11"

假设要创建校验查询参数 `q` 是否包含固定内容的依赖项。

但此处要把待检验的固定内容定义为参数。

## **可调用**实例

Python 可以把类实例变为**可调用项**。

这里说的不是类本身（类本就是可调用项），而是类实例。

为此，需要声明 `__call__` 方法：

```Python hl_lines="10"
{!../../docs_src/dependencies/tutorial011.py!}
```

本例中，**FastAPI**  使用 `__call__` 检查附加参数及子依赖项，稍后，还要调用它向*路径操作函数*传递值。

## 参数化实例

接下来，使用 `__init__` 声明用于**参数化**依赖项的实例参数：

```Python hl_lines="7"