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"}

			"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",

# 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.

Asynchronous code just means that the language 💬 has a way to tell the computer / program 🤖 that at some point in the code, it 🤖 will have to wait for *something else* to finish somewhere else. Let's say that *something else* is called "slow-file" 📝.

So, during that time, the computer can go and do some other work, while "slow-file" 📝 finishes.

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

name: Regression
description: Report a problem about something that used to work
labels: [ "a:regression", "to-triage" ]
assignees: [ ]
body:
  - type: markdown
    attributes:
      value: |
        Please use our bug report template to report problems with something that has never worked.
        Regressions reports are greatly appreciated during our RC phase and before a final release.
  - type: textarea
    id: current-behavior
    attributes:

app = FastAPI()


def get_header(*, someheader: str = Header()):
    return someheader


def get_something_else(*, someheader: str = Depends(get_header)):
    return f"{someheader}123"


@app.get("/")
def get_deps(dep1: str = Depends(get_header), dep2: str = Depends(get_something_else)):
    return {"dep1": dep1, "dep2": dep2}


client = TestClient(app)

schema = {
    "components": {

### Async Context Manager

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

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

```Python hl_lines="1  13"
{!../../../docs_src/events/tutorial003.py!}
```

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:

    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);
  }

The server handler function has this signature: `type SingleHandlerFn func(payload []byte) ([]byte, *RemoteErr)`.

Sample handler:
```go
    handler :=  func(payload []byte) ([]byte, *grid.RemoteErr) {
        // Do something with payload
        return []byte("response"), nil
    }

    err := manager.RegisterSingleHandler(grid.HandlerDiskInfo, handler)
```

Sample call:
```go
    // Get a connection to the remote host