Wie funktioniert das? Schauen wir uns das mal an. 🤓

### Typannotationen und Tooling { #type-annotations-and-tooling }

Sehen wir uns zunächst an, wie Editor, mypy und andere Tools dies sehen würden.

**Note**: Make sure you put `"fastapi[standard]"` in quotes to ensure it works in all terminals.

## Example { #example }

### Create it { #create-it }

Create a file `main.py` with:

```Python
from typing import Union

from fastapi import FastAPI

app = FastAPI()


@app.get("/")
def read_root():
    return {"Hello": "World"}


@app.get("/items/{item_id}")

// ARM64SpecialOperand returns the internal representation of a special operand.
func ARM64SpecialOperand(name string) arm64.SpecialOperand {
	if arm64SpecialOperand == nil {
		// Generate mapping when function is first called.
		arm64SpecialOperand = map[string]arm64.SpecialOperand{}
		for opd := arm64.SPOP_BEGIN; opd < arm64.SPOP_END; opd++ {
			arm64SpecialOperand[opd.String()] = opd
		}

## Пример { #example }

### Создание { #create-it }

Создайте файл `main.py` со следующим содержимым:

```Python
from typing import Union

from fastapi import FastAPI

app = FastAPI()


@app.get("/")
def read_root():
    return {"Hello": "World"}


@app.get("/items/{item_id}")

* Валідація **складних структур**:
    * Використання ієрархічних моделей Pydantic. Python `typing`, `List` і `Dict` тощо.
    * Валідатори дозволяють чітко і просто визначати, перевіряти й документувати складні схеми даних у вигляді JSON-схеми.

import org.eclipse.aether.util.ConfigUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * Maven G level metadata generator.
 * <p>
 * Plugin metadata contains G level list of "prefix" to A mapping for plugins present under this G.
 *
 * @deprecated since 4.0.0, use {@code maven-api-impl} jar instead
 */
@Deprecated(since = "4.0.0")
class PluginsMetadataGenerator implements MetadataGenerator {

  cp_normalized_srcjar bazel-bin/tensorflow/java/libtensorflow-src.jar "${DIR}/libtensorflow-src.jar"
  cp bazel-bin/tensorflow/tools/lib_package/libtensorflow_proto.zip "${DIR}"
else
  # Temporary directory for package zipping
  LIB_PKG="$DIR/lib_package"
  mkdir -p ${LIB_PKG}

  # Zip up the .dll and the LICENSE for the JNI library.
  cp bazel-bin/tensorflow/java/tensorflow_jni.dll ${LIB_PKG}/tensorflow_jni.dll

/// tip

The `shutdown` would happen when you are **stopping** the application.

Maybe you need to start a new version, or you just got tired of running it. 🤷

///

### Lifespan function { #lifespan-function }

			}
			if objectName != testCase.object {
				t.Errorf("failed expected bucket name \"%s\", got \"%s\"", testCase.object, objectName)
			}
		})
	}
}

// Add tests for starting and stopping different profilers.
func TestStartProfiler(t *testing.T) {
	_, err := startProfiler("")
	if err == nil {
		t.Fatal("Expected a non nil error, but nil error returned for invalid profiler.")
	}
}

from typing import Annotated, Optional

import pytest
from fastapi import FastAPI, Header
from fastapi.testclient import TestClient
from pydantic import BaseModel, Field

app = FastAPI()

# =====================================================================================
# Without aliases


@app.get("/optional-list-str")
async def read_optional_list_str(
    p: Annotated[Optional[list[str]], Header()] = None,
):