class Item(BaseModel):
    name: str

    if PYDANTIC_V2:
        model_config = {
            "json_schema_extra": {
                "x-something-internal": {"level": 4},
            }
        }
    else:

        class Config:
            schema_extra = {
                "x-something-internal": {"level": 4},
            }


@app.get("/foo", response_model=Item)
def foo():
    return {"name": "Foo item"}

      Stopwatch s = Stopwatch.createStarted();
      // here is where you would do something
      total += s.elapsed(NANOSECONDS);
    }
    return total;
  }

  @Benchmark
  long manual(int reps) {
    long total = 0;
    for (int i = 0; i < reps; i++) {
      long start = System.nanoTime();
      // here is where you would do something
      total += (System.nanoTime() - start);
    }
    return total;
  }

      Stopwatch s = Stopwatch.createStarted();
      // here is where you would do something
      total += s.elapsed(NANOSECONDS);
    }
    return total;
  }

  @Benchmark
  long manual(int reps) {
    long total = 0;
    for (int i = 0; i < reps; i++) {
      long start = System.nanoTime();
      // here is where you would do something
      total += (System.nanoTime() - start);
    }
    return total;
  }

            "age": "70",
            "tags": ["plumbus", "citadel"],
            "with": "something",
        },
    )
    assert response.status_code == 200, response.text
    assert response.json() == {
        "username": "Rick",
        "lastname": "Sanchez",
        "age": 70,
        "tags": ["plumbus", "citadel"],
        "with": "something",
    }


def test_defaults():

			"sidecar.istio.io/status": "something",
		},
		Labels: map[string]string{
			"testlabel": "true",
		},
		NodeName:            "test-node",
		InitContainerStatus: &brokenInitContainerTerminating,
	})

	brokenPodWaiting = makePod(makePodArgs{
		PodName: "broken-pod-waiting",
		Annotations: map[string]string{
			"sidecar.istio.io/status": "something",
		},
		NodeName:            "test-node",

### Async Context Manager

If you check, the function is decorated with an `@asynccontextmanager`.

That converts the function into something called an "**async context manager**".

{* ../../docs_src/events/tutorial003.py hl[1,13] *}

A **context manager** in Python is something that you can use in a `with` statement, for example, `open()` can be used as a context manager:

```Python
with open("file.txt") as file:

    val handshake = makeRequest(client)

    assertThat(handshake.cipherSuite).isIn(*expectedModernTls12CipherSuites.toTypedArray())

    // Probably something like
    // TLS_AES_128_GCM_SHA256
    // TLS_AES_256_GCM_SHA384
    // TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384
    // TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256
    // TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384

    return suite;
  }

  private static final String STRING = ASCII + I18N;
  private static final String LINES = "foo\nbar\r\nbaz\rsomething";
  private static final ImmutableList<String> SPLIT_LINES =
      ImmutableList.of("foo", "bar", "baz", "something");

  private TestCharSource source;

  @Override
  public void setUp() {
    source = new TestCharSource(STRING);
  }

At that point, by noticing that the server took some microseconds longer to send the "Incorrect username or password" response, the attackers will know that they got _something_ right, some of the initial letters were right.

And then they can try again knowing that it's probably something more similar to `stanleyjobsox` than to `johndoe`.

#### A "professional" attack

# JSON Compatible Encoder

There are some cases where you might need to convert a data type (like a Pydantic model) to something compatible with JSON (like a `dict`, `list`, etc).

For example, if you need to store it in a database.

For that, **FastAPI** provides a `jsonable_encoder()` function.

## Using the `jsonable_encoder`

Let's imagine that you have a database `fake_db` that only receives JSON compatible data.