class Offer(BaseModel):
    name: str
    description: str | None = None
    price: float
    items: list[Item]


@app.post("/offers/")
async def create_offer(offer: Offer):

        // If there's a "Expect: 100-continue" header on the request, wait for a "HTTP/1.1 100
        // Continue" response before transmitting the request body. If we don't get that, return
        // what we did get (such as a 4xx response) without ever transmitting the request body.
        if ("100-continue".equals(request.header("Expect"), ignoreCase = true)) {
          exchange.flushRequest()

    Entry<String, Integer> entry =
        new AbstractMapEntry<String, Integer>() {
          @Override
          public String getKey() {
            return holder.string;
          }

          @Override
          public Integer getValue() {
            return 1;
          }
        };

    builder.put(entry);
    holder.string = "two";
    assertEquals(asList(1), builder.build().get("one"));
  }

			metaArr[i].TransitionStatus = ""
		}
		return metaArr
	}
	mkParities := func(N, agreedParity, disagreedParity, agree int) []int {
		ps := make([]int, N)
		for i := range N {
			if i < agree {
				ps[i] = agreedParity
				continue
			}
			ps[i] = disagreedParity // disagree
		}
		return ps
	}

	mkTest := func(N, parity, agree int) (res struct {

from fastapi import FastAPI, status

app = FastAPI()


@app.post("/items/", status_code=status.HTTP_201_CREATED)
async def create_item(name: str):

from fastapi import FastAPI

app = FastAPI()


@app.get("/items/", operation_id="some_specific_id_you_define")
async def read_items():

    price: float
    is_offer: bool = None


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


@app.get("/items/{item_id}")
def read_item(item_id: int, q: str = None):
    return {"item_id": item_id, "q": q}


@app.put("/items/{item_id}")
def update_item(item_id: int, item: Item):
    return {"item_name": item.name, "item_id": item_id}
```

    * As connecting to an email server and sending an email tends to be "slow" (several seconds), you can return the response right away and send the email notification in the background.
* Processing data:
    * For example, let's say you receive a file that must go through a slow process, you can return a response of "Accepted" (HTTP 202) and process the file in the background.

## Using `BackgroundTasks`

from fastapi import APIRouter, Body

router = APIRouter()


@router.post("/compute")
def compute(a: int = Body(), b: str = Body()):

from typing import Dict

from fastapi import FastAPI

app = FastAPI()


@app.post("/index-weights/")
async def create_index_weights(weights: Dict[int, float]):