```Python hl_lines="4  9-12  25-27"
from typing import Union

from fastapi import FastAPI
from pydantic import BaseModel

app = FastAPI()


class Item(BaseModel):
    name: str
    price: float
    is_offer: Union[bool, None] = None


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


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

    //                                                                            ========
    /**
     * {@inheritDoc} <br>
     * Application Origin Methods:
     * <pre>
     * <span style="font-size: 130%; color: #553000">[Small Helper]</span>
     * o saveInfo() <span style="color: #3F7E5E">// save messages to session</span>

settings from. This allows setting the GODEBUG defaults separately
from the Go language version in the module.
In this example, the program is asking for Go 1.21 semantics and
then asking for the old pre-Go 1.21 `panic(nil)` behavior and the
new Go 1.23 `asynctimerchan=0` behavior.

Only the work module's `go.mod` is consulted for `godebug` directives.
Any directives in required dependency modules are ignored.

    protected static final String SPNEGO_ALLOW_BASIC = "spnego.allow.basic";

    /** Configuration key for pre-authentication password. */
    protected static final String SPNEGO_PREAUTH_PASSWORD = "spnego.preauth.password";

    /** Configuration key for pre-authentication username. */
    protected static final String SPNEGO_PREAUTH_USERNAME = "spnego.preauth.username";

    public static final char[] HEX_DIGITS = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' };

    /**
     * Generate "hexdump" output of the buffer at src like the following:
     *
     * <pre>
     * 00000: 04 d2 29 00 00 01 00 00 00 00 00 01 20 45 47 46  |..)......... EGF|
     * 00010: 43 45 46 45 45 43 41 43 41 43 41 43 41 43 41 43  |CEFEECACACACACAC|

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import jcifs.CIFSException;
import jcifs.internal.smb2.nego.PreauthIntegrityNegotiateContext;

/**
 * Enhanced Pre-Authentication Integrity Service for SMB 3.1.1.
 *
 * Provides comprehensive pre-authentication integrity protection against
 * downgrade attacks by maintaining cryptographic hash chains of all
 * negotiation and session setup messages.
 */

También obtendrás autocompletado para el payload a enviar:

<img src="/img/tutorial/generate-clients/image03.png">

/// tip | Consejo

Nota el autocompletado para `name` y `price`, que fue definido en la aplicación de FastAPI, en el modelo `Item`.

///

Tendrás errores en línea para los datos que envíes:

<img src="/img/tutorial/generate-clients/image04.png">

```Python hl_lines="2  7 8 9 10  23 24 25"
from fastapi import FastAPI
from pydantic import BaseModel

app = FastAPI()


class Item(BaseModel):
    name: str
    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):

   * unspecified if this method is called more than once on the same instance.
   */
  public HashCode hash() {
    return hasher.hash();
  }

  // Overriding close() because FilterOutputStream's close() method pre-JDK8 has bad behavior:
  // it silently ignores any exception thrown by flush(). Instead, just close the delegate stream.
  // It should flush itself if necessary.
  @Override
  public void close() throws IOException {

{* ../../docs_src/dependencies/tutorial011_an_py39.py hl[9] *}

Neste caso, o **FastAPI** nunca tocará ou se importará com o `__init__`, nós vamos utilizar diretamente em nosso código.

## Crie uma instância { #create-an-instance }

Nós poderíamos criar uma instância desta classe com:

{* ../../docs_src/dependencies/tutorial011_an_py39.py hl[18] *}