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.

For example, it doesn't receive `datetime` objects, as those are not compatible with JSON.

   * implementation, because {@code map.get()} returns a view collection that changes in the course
   * of a call to {@code remove()}. Thus, the expectation doesn't hold that {@code map.remove(x)}
   * returns the same value which {@code map.get(x)} did immediately beforehand.
   */
  @Override
  public void testRemove() {
    final Map<String, Collection<Integer>> map;

## What it does

It will go and look in the request for that `Authorization` header, check if the value is `Bearer ` plus some token, and will return the token as a `str`.

If it doesn't see an `Authorization` header, or the value doesn't have a `Bearer ` token, it will respond with a 401 status code error (`UNAUTHORIZED`) directly.

 * incoming messages. But it does not guarantee that the other peer will successfully receive all of
 * its incoming messages.
 */
interface WebSocket {
  /** Returns the original request that initiated this web socket. */
  fun request(): Request

  /**
   * Returns the size in bytes of all messages enqueued to be transmitted to the server. This

    // Exists to test that our framework doesn't run it:
    @SuppressWarnings("unused")
    @ExampleDerivedFeature.Require({
      ExampleDerivedFeature.DERIVED_FEATURE_1,
      ExampleDerivedFeature.DERIVED_FEATURE_2
    })
    public void testRequiringTwoExplicitDerivedFeatures() throws Exception {
      doNotActuallyRunThis();
    }

    // Exists to test that our framework doesn't run it:
    @SuppressWarnings("unused")

    with the API key and integrates that into the OpenAPI documentation. It extracts
    the key value sent in the query parameter automatically and provides it as the
    dependency result. But it doesn't define how to send that API key to the client.

    ## Usage

    Create an instance object and use that object as the dependency in `Depends()`.

    The dependency result will be a string containing the key value.

 *
 * @author Louis Wasserman
 */
@GwtCompatible(emulated = true)
@ElementTypesAreNonnullByDefault
public class MultimapBuilderTest extends TestCase {

  @J2ktIncompatible
  @GwtIncompatible // doesn't build without explicit type parameters on build() methods
  public void testGenerics() {
    ListMultimap<String, Integer> a = MultimapBuilder.hashKeys().arrayListValues().build();

        * **FastAPI**: (uses Starlette) an API microframework with several additional features for building APIs, with data validation, etc.

* **Uvicorn**:
    * Will have the best performance, as it doesn't have much extra code apart from the server itself.

		return consumed, nil, typ, err
	}

	return consumed, nameBuf[:nameLen], typ, nil
}

// readDirFn applies the fn() function on each entries at dirPath, doesn't recurse into
// the directory itself, if the dirPath doesn't exist this function doesn't return
// an error.
func readDirFn(dirPath string, fn func(name string, typ os.FileMode) error) error {
	fd, err := openFileWithFD(dirPath, readMode, 0o666)
	if err != nil {

This client could be a browser with a frontend, a code from someone else, an IoT device, etc.

You could need to tell the client that:

* The client doesn't have enough privileges for that operation.
* The client doesn't have access to that resource.
* The item the client was trying to access doesn't exist.
* etc.

In these cases, you would normally return an **HTTP status code** in the range of **400** (from 400 to 499).