//// tab | Python 3.9+

```Python hl_lines="12"
{!> ../../docs_src/security/tutorial001_an_py39.py!}
```

////

//// tab | Python 3.8+

```Python hl_lines="11"
{!> ../../docs_src/security/tutorial001_an.py!}
```

////

//// tab | Python 3.8+ nicht annotiert

/// tip | "Tipp"

//// tab | Python 3.9+

```Python hl_lines="12"
{!> ../../docs_src/security/tutorial001_an_py39.py!}
```

////

//// tab | Python 3.8+

```Python hl_lines="11"
{!> ../../docs_src/security/tutorial001_an.py!}
```

////

//// tab | Python 3.8+ non-Annotated

/// tip

Prefer to use the `Annotated` version if possible.

//// tab | Linux, macOS, Windows Bash

<div class="termy">

```console
// Je zou een omgevingsvariabele MY_NAME kunnen maken met
$ export MY_NAME="Wade Wilson"

// Dan zou je deze met andere programma's kunnen gebruiken, zoals
$ echo "Hello $MY_NAME"

Hello Wade Wilson
```

</div>

////

//// tab | Windows PowerShell

<div class="termy">

//// tab | Linux, macOS, Windows Bash

<div class="termy">

```console
// You could create an env var MY_NAME with
$ export MY_NAME="Wade Wilson"

// Then you could use it with other programs, like
$ echo "Hello $MY_NAME"

Hello Wade Wilson
```

</div>

////

//// tab | Windows PowerShell

<div class="termy">

```console

### `OAuth2PasswordRequestForm`

🥇, 🗄 `OAuth2PasswordRequestForm`, & ⚙️ ⚫️ 🔗 ⏮️ `Depends` *➡ 🛠️* `/token`:

//// tab | 🐍 3️⃣.6️⃣ & 🔛

```Python hl_lines="4  76"
{!> ../../docs_src/security/tutorial003.py!}
```

////

//// tab | 🐍 3️⃣.1️⃣0️⃣ & 🔛

```Python hl_lines="2  74"
{!> ../../docs_src/security/tutorial003_py310.py!}
```

////

		return false
	}

	if len(ef.Tags) > 0 && !obj.DeleteMarker {
		// Only parse object tags if tags filter is specified.
		var tagMap map[string]string
		if len(obj.UserTags) != 0 {
			t, err := tags.ParseObjectTags(obj.UserTags)
			if err != nil {
				return false
			}
			tagMap = t.ToMap()
		}

		for _, kv := range ef.Tags {
			// Object (version) must match all tags specified in
			// the filter

//// tab | Python 3.9+

```Python hl_lines="6  12-13"
{!> ../../docs_src/settings/app02_an_py39/main.py!}
```

////

//// tab | Python 3.8+

```Python hl_lines="6  12-13"
{!> ../../docs_src/settings/app02_an/main.py!}
```

////

//// tab | Python 3.8+ nicht annotiert

/// tip | "Tipp"

//// tab | python 3.9+

```python hl_lines="6  14  22"
{!> ../../docs_src/dependencies/tutorial008_an_py39.py!}
```

////

//// tab | python 3.8+

```python hl_lines="5  13  21"
{!> ../../docs_src/dependencies/tutorial008_an.py!}
```

////

//// tab | python 3.8+ non-annotated

/// tip | "Dica"

## Необязательные параметры

Аналогично, вы можете объявлять необязательные query-параметры, установив их значение по умолчанию, равное `None`:

//// tab | Python 3.10+

```Python hl_lines="7"
{!> ../../docs_src/query_params/tutorial002_py310.py!}
```

////

//// tab | Python 3.8+

```Python hl_lines="9"
{!> ../../docs_src/query_params/tutorial002.py!}
```

////

```

查询参数的值就是：

* `skip=20`：在 URL 中设定的值
* `limit=10`：使用默认值

## 可选参数

同理，把默认值设为 `None` 即可声明**可选的**查询参数：

//// tab | Python 3.10+

```Python hl_lines="7"
{!> ../../docs_src/query_params/tutorial002_py310.py!}
```

////

//// tab | Python 3.8+

```Python hl_lines="9"
{!> ../../docs_src/query_params/tutorial002.py!}
```

////

本例中，查询参数 `q` 是可选的，默认值为 `None`。