from pydantic import Discriminator, Tag

    class Cat(BaseModel):
        pet_type: str = "cat"
        meows: int

    class Dog(BaseModel):
        pet_type: str = "dog"
        barks: float

    def get_pet_type(v):
        assert isinstance(v, dict)
        return v.get("pet_type", "")

    Pet = Annotated[
        Union[Annotated[Cat, Tag("cat")], Annotated[Dog, Tag("dog")]],

from fastapi.testclient import TestClient
from pydantic import BaseModel, HttpUrl

app = FastAPI()


class Invoice(BaseModel):
    id: str
    title: Optional[str] = None
    customer: str
    total: float


class InvoiceEvent(BaseModel):
    description: str
    paid: bool


class InvoiceEventReceived(BaseModel):
    ok: bool


invoices_callback_router = APIRouter()

    // The values here look like 111...11101...010 in binary, where the initial 111...1110 takes
    // up exactly as many bits as can be represented in the significand (24 for float, 53 for
    // double). That final 0 should be rounded up to 1 because the remaining bits make that number
    // slightly nearer.
    long floatConversionTest = 0xfffffe8000000002L;

    }

    @Override
    public MetadataGenerator newInstance(RepositorySystemSession session, DeployRequest request) {
        return new PluginsMetadataGenerator(session, request);
    }

    @Override
    public float getPriority() {
        return 10; // G level MD should be deployed as 3rd MD
    }

    @Override
    public MetadataGenerator newInstance(RepositorySystemSession session, DeployRequest request) {
        return new RemoteSnapshotMetadataGenerator(session, request);
    }

    @Override
    public float getPriority() {
        return 30; // GAV level metadata should be deployed 1st MD
    }

    @Override
    public MetadataGenerator newInstance(RepositorySystemSession session, DeployRequest request) {
        return new VersionsMetadataGenerator(session, request);
    }

    @Override
    public float getPriority() {
        return 20; // GA level metadata should be deployed 2nd MD
    }

from fastapi import APIRouter, FastAPI
from pydantic import BaseModel, HttpUrl

app = FastAPI()


class Invoice(BaseModel):
    id: str
    title: Union[str, None] = None
    customer: str
    total: float


class InvoiceEvent(BaseModel):
    description: str
    paid: bool


class InvoiceEventReceived(BaseModel):
    ok: bool


invoices_callback_router = APIRouter()

     *
     * <p>It is strongly encouraged to use {@link #add(String, float)} instead and give value a
     * readable name.
     *
     * @since 18.0 (since 11.0 as {@code Objects.ToStringHelper.addValue()}).
     */
    @CanIgnoreReturnValue
    public ToStringHelper addValue(float value) {
      return addUnconditionalHolder(String.valueOf(value));
    }

    /**

* `le`: `l`ess than or `e`qual (менше або дорівнює)

{* ../../docs_src/path_params_numeric_validations/tutorial005_an_py39.py hl[10] *}

## Валідація числових даних: float, більше ніж і менше ніж

Валідація чисел також працює для значень типу `float`.

from typing import Optional

from fastapi import FastAPI
from fastapi.testclient import TestClient
from pydantic import BaseModel

app = FastAPI()


class Item(BaseModel):
    name: str
    price: Optional[float] = None
    owner_ids: Optional[list[int]] = None


@app.get("/items/valid", response_model=Item)
def get_valid():
    return {"name": "valid", "price": 1.0}


@app.get("/items/coerce", response_model=Item)