from typing import Optional

import pytest
from fastapi import FastAPI
from fastapi.exceptions import ResponseValidationError
from fastapi.testclient import TestClient
from pydantic.dataclasses import dataclass

app = FastAPI()


@dataclass
class Item:
    name: str
    price: Optional[float] = None
    owner_ids: Optional[list[int]] = None


@app.get("/items/invalid", response_model=Item)
def get_invalid():

from typing import Optional


def get_authorization_scheme_param(
    authorization_header_value: Optional[str],
) -> tuple[str, str]:
    if not authorization_header_value:
        return "", ""
    scheme, _, param = authorization_header_value.partition(" ")

     *
     * @return the optional POM file
     */
    @Nonnull
    Optional<Path> getPomFile();

    /**
     * Gets the project that was built.
     *
     * @return The project that was built or {@code null} if an error occurred and this result accompanies a
     *         {@link ProjectBuilderException}.
     */
    @Nonnull
    Optional<Project> getProject();

    /**

# Apache Maven Debug Script
#
# Environment Variable Prerequisites
#
#   JAVA_HOME           (Optional) Points to a Java installation.
#   MAVEN_OPTS          (Optional) Java runtime options used when Maven is executed.
#   MAVEN_SKIP_RC       (Optional) Flag to disable loading of mavenrc files.
#   MAVEN_DEBUG_ADDRESS (Optional) Set the debug address. Default value is localhost:8000

```Python hl_lines="1  4"
{!../../docs_src/python_types/tutorial009_py39.py!}
```

O uso de `Optional[str]` em vez de apenas `str` permitirá que o editor o ajude a detectar erros, onde você pode estar assumindo que um valor é sempre um `str`, quando na verdade também pode ser `None`.

```

////

#### Uso de `Union` u `Optional` { #using-union-or-optional }

Si estás usando una versión de Python inferior a 3.10, aquí tienes un consejo desde mi punto de vista muy **subjetivo**:

* 🚨 Evita usar `Optional[SomeType]`
* En su lugar ✨ **usa `Union[SomeType, None]`** ✨.

        void shouldBeApplicableWhenModelOptionTrue() {
            UpgradeOptions options = mock(UpgradeOptions.class);
            when(options.model()).thenReturn(Optional.of(true));
            when(options.all()).thenReturn(Optional.empty());

            UpgradeContext context = createMockContext(options);

            assertTrue(strategy.isApplicable(context), "Strategy should be applicable when --model is true");

from typing import Optional

from fastapi import Depends, FastAPI, Security
from fastapi.security.open_id_connect_url import OpenIdConnect
from fastapi.testclient import TestClient
from pydantic import BaseModel

app = FastAPI()

oid = OpenIdConnect(openIdConnectUrl="/openid", auto_error=False)


class User(BaseModel):
    username: str


def get_current_user(oauth_header: Optional[str] = Security(oid)):
    if oauth_header is None:

package org.apache.maven.cling.invoker.cisupport;

import java.util.Optional;

import org.apache.maven.api.cli.cisupport.CIInfo;

/**
 * TeamCity CI support.
 */
public class TeamcityCIDetector implements CIDetector {
    public static final String NAME = "TeamCity";

    private static final String TEAMCITY_VERSION = "TEAMCITY_VERSION";

    @Override
    public Optional<CIInfo> detectCI() {

import org.codelibs.fess.util.ComponentUtil;
import org.codelibs.fess.util.DocumentUtil;
import org.codelibs.fess.util.FacetResponse;
import org.dbflute.optional.OptionalEntity;
import org.dbflute.optional.OptionalThing;
import org.lastaflute.web.util.LaRequestUtil;
import org.opensearch.action.search.SearchRequestBuilder;
import org.opensearch.action.search.SearchResponse;