* Swagger UI.
    * ReDoc.

---

Um auf das vorherige Codebeispiel zurückzukommen, **FastAPI** wird:

* Validieren, dass es eine `item_id` im Pfad für `GET`- und `PUT`-Requests gibt.
* Validieren, ob die `item_id` vom Typ `int` für `GET`- und `PUT`-Requests ist.
    * Falls nicht, sieht der Client einen hilfreichen, klaren Fehler.

```python
from fastapi import APIRouter
```

::: fastapi.APIRouter
    options:
        members:
            - websocket
            - include_router
            - get
            - put
            - post
            - delete
            - options
            - head
            - patch
            - trace

from fastapi.responses import JSONResponse
from pydantic import BaseModel


class Item(BaseModel):
    title: str
    timestamp: datetime
    description: str | None = None


app = FastAPI()


@app.put("/items/{id}")
def update_item(id: str, item: Item):
    json_compatible_item_data = jsonable_encoder(item)

        for (int i = 1; key != null || value != null; i++) {
            List values = (List) map.get(key);
            if (values == null) {
                values = new ArrayList();
                map.put(key, values);
            }
            values.add(value);
            key = connection.getHeaderFieldKey(i);
            value = connection.getHeaderField(i);
        }

  @ParametricNullness
  public final T next() {
    if (!hasNext()) {
      throw new NoSuchElementException();
    }
    state = State.NOT_READY;
    // Safe because hasNext() ensures that tryToComputeNext() has put a T into `next`.
    T result = uncheckedCastNullableTToT(next);
    next = null;
    return result;
  }

  /**
   * Returns the next element in the iteration without advancing the iteration, according to the

class Item(BaseModel):
    name: str
    description: str | None = None
    price: float
    tax: float | None = None


class User(BaseModel):
    username: str
    full_name: str | None = None


@app.put("/items/{item_id}")
async def update_item(item_id: int, item: Item, user: User):
    results = {"item_id": item_id, "item": item, "user": user}

unpack it into /usr/local/go, or if you rebuild from sources by running all.bash (see doc/install.html). You should also add the Go binary directory $GOROOT/bin to your shell's path. For example, if you extracted the tar file into $HOME/go, you might put the following in your .profile: export GOROOT=$HOME/go export PATH=$PATH:$GOROOT/bin See doc/install.html for more details....

class Item(BaseModel):
    name: str
    description: str | None = None
    price: float
    tax: float | None = None
    tags: set[str] = set()
    images: list[Image] | None = None


@app.put("/items/{item_id}")
async def update_item(item_id: int, item: Item):
    results = {"item_id": item_id, "item": item}

        if (valueEquivalence.equivalent(leftValue, rightValue)) {
          onBoth.put(leftKey, leftValue);
        } else {
          differences.put(leftKey, ValueDifferenceImpl.create(leftValue, rightValue));
        }
      } else {
        onlyOnLeft.put(leftKey, leftValue);
      }
    }
  }

        if (valueEquivalence.equivalent(leftValue, rightValue)) {
          onBoth.put(leftKey, leftValue);
        } else {
          differences.put(leftKey, ValueDifferenceImpl.create(leftValue, rightValue));
        }
      } else {
        onlyOnLeft.put(leftKey, leftValue);
      }
    }
  }