FastAPI converts the configurations to **JSON** to make them compatible with JavaScript, as that's what Swagger UI needs.

## Disable Syntax Highlighting { #disable-syntax-highlighting }

For example, you could disable syntax highlighting in Swagger UI.

Without changing the settings, syntax highlighting is enabled by default:

<img src="/img/tutorial/extending-openapi/image02.png">

#### Liste

Definieren wir zum Beispiel eine Variable, die eine `list` von `str` – eine Liste von Strings – sein soll.

//// tab | Python 3.9+

Deklarieren Sie die Variable mit der gleichen Doppelpunkt-Syntax (`:`).

Als Typ nehmen Sie `list`.

#### List { #list }

For example, let's define a variable to be a `list` of `str`.

//// tab | Python 3.9+

Declare the variable, with the same colon (`:`) syntax.

As the type, put `list`.

			case ')':
				tok = in.Stack.Next() // First token of macro definition.
				break Loop
			case ',':
				if acceptArg {
					in.Error("bad syntax in definition for macro:", name)
				}
				acceptArg = true
			case scanner.Ident:
				if !acceptArg {
					in.Error("bad syntax in definition for macro:", name)
				}
				arg := in.Stack.Text()
				if slices.Contains(args, arg) {

```Python
my_list: list[str]
```

In versions of Python before 3.9, it would be:

```Python
from typing import List

my_list: List[str]
```

That's all standard Python syntax for type declarations.

Use that same standard syntax for model attributes with internal types.

So, in our example, we can make `tags` be specifically a "list of strings":

{* ../../docs_src/body_nested_models/tutorial002_py310.py hl[12] *}

In Python 3.9 wäre das:

```Python
my_list: list[str]
```

Und in Python-Versionen vor 3.9:

```Python
from typing import List

my_list: List[str]
```

Das ist alles Standard-Python-Syntax für Typdeklarationen.

Verwenden Sie dieselbe Standardsyntax für Modellattribute mit inneren Typen.

In unserem Beispiel können wir also bewirken, dass `tags` spezifisch eine „Liste von Strings“ ist:

                    withPendingChangesOnly = branch.isMainBranch
                    enabled = branch.enableVcsTriggers
                    // https://www.jetbrains.com/help/teamcity/2022.04/configuring-schedule-triggers.html#general-syntax-1
                    // We want it to be triggered only when there're pending changes in the specific vcs root, i.e. GradleMaster/GradleRelease

![ReDoc](https://fastapi.tiangolo.com/img/index/index-06-redoc-02.png)

### Gewoon Moderne Python

Het is allemaal gebaseerd op standaard **Python type** declaraties (dankzij Pydantic). Je hoeft dus geen nieuwe syntax te leren. Het is gewoon standaard moderne Python.

#### List

Laten we bijvoorbeeld een variabele definiëren als een `list` van `str`.

//// tab | Python 3.9+

Declareer de variabele met dezelfde dubbele punt (`:`) syntax.

Als type, vul `list` in.

# Concurrency and async / await { #concurrency-and-async-await }

Details about the `async def` syntax for *path operation functions* and some background about asynchronous code, concurrency, and parallelism.

## In a hurry? { #in-a-hurry }

<abbr title="too long; didn't read"><strong>TL;DR:</strong></abbr>

If you are using third party libraries that tell you to call them with `await`, like:

```Python
results = await some_library()
```