# Additional Status Codes

By default, **FastAPI** will return the responses using a `JSONResponse`, putting the content you return from your *path operation* inside of that `JSONResponse`.

It will use the default status code or the one you set in your *path operation*.

## Additional status codes

```Python hl_lines="8-13"
{!../../../docs_src/sql_databases/sql_app/tests/test_sql_app.py!}
```

!!! tip
    You could reduce duplication in that code by putting it in a function and using it from both `database.py` and `tests/test_sql_app.py`.

    For simplicity and to focus on the specific testing code, we are just copying it.

## Create the database

    "JDK_HOME",
    "JRE_HOME",
    "CommonProgramFiles",
    "CommonProgramFiles(x86)",
    "CommonProgramW6432",
    "ProgramData",
    "ProgramFiles",
    "ProgramFiles(x86)",
    // Simply putting PATH there isn't enough. Windows has case-insensitive env vars but something else fails if the Path variable is published as PATH for test tasks.
    OperatingSystem.current().pathVar,
    "PATHEXT",
)

We create an async function `lifespan()` with `yield` like this:

```Python hl_lines="16  19"
{!../../../docs_src/events/tutorial003.py!}
```

Here we are simulating the expensive *startup* operation of loading the model by putting the (fake) model function in the dictionary with machine learning models before the `yield`. This code will be executed **before** the application **starts taking requests**, during the *startup*.

  for (i in 0 until length) {
    val c = this[i]
    if (c <= '\u001f' || c >= '\u007f') {
      return i
    }
  }
  return -1
}

/** Returns true if we should void putting this this header in an exception or toString(). */
internal fun isSensitiveHeader(name: String): Boolean {
  return name.equals("Authorization", ignoreCase = true) ||
    name.equals("Cookie", ignoreCase = true) ||

  // The webhook cares about an operation if it matches _any_ Rule.
  // However, in order to prevent ValidatingAdmissionWebhooks and MutatingAdmissionWebhooks
  // from putting the cluster in a state which cannot be recovered from without completely
  // disabling the plugin, ValidatingAdmissionWebhooks and MutatingAdmissionWebhooks are never called

  // The webhook cares about an operation if it matches _any_ Rule.
  // However, in order to prevent ValidatingAdmissionWebhooks and MutatingAdmissionWebhooks
  // from putting the cluster in a state which cannot be recovered from without completely
  // disabling the plugin, ValidatingAdmissionWebhooks and MutatingAdmissionWebhooks are never called

    ```

### `Union` in Python 3.10

In this example we pass `Union[PlaneItem, CarItem]` as the value of the argument `response_model`.

Because we are passing it as a **value to an argument** instead of putting it in a **type annotation**, we have to use `Union` even in Python 3.10.

If it was in a type annotation we could have used the vertical bar, as:

```Python
some_variable: PlaneItem | CarItem
```

    public EntryComparator(@Nullable Comparator<? super K> keyComparator) {
      this.keyComparator = keyComparator;
    }

    @Override
    @SuppressWarnings("unchecked") // no less safe than putting it in the map!
    public int compare(Entry<K, V> a, Entry<K, V> b) {
      return (keyComparator == null)
          ? ((Comparable) a.getKey()).compareTo(b.getKey())
          : keyComparator.compare(a.getKey(), b.getKey());

    }

    @Override
    @ParametricNullness
    public T get() {
      // Another variant of Double Checked Locking.
      //
      // We use two volatile reads. We could reduce this to one by
      // putting our fields into a holder class, but (at least on x86)
      // the extra memory consumption and indirection are more
      // expensive than the extra volatile reads.
      long nanos = expirationNanos;