/**
   * Compares the specified object to this multimap for equality.
   *
   * <p>Two {@code SetMultimap} instances are equal if, for each key, they contain the same values.
   * Equality does not depend on the ordering of keys or values.
   *
   * <p>An empty {@code SetMultimap} is equal to any other empty {@code Multimap}, including an
   * empty {@code ListMultimap}.
   */
  @Override

  /**
   * Compares the specified object to this multimap for equality.
   *
   * <p>Two {@code SetMultimap} instances are equal if, for each key, they contain the same values.
   * Equality does not depend on the ordering of keys or values.
   *
   * <p>An empty {@code SetMultimap} is equal to any other empty {@code Multimap}, including an
   * empty {@code ListMultimap}.
   */
  @Override

In most cases you would (and should) have a "termination proxy" handling HTTPS for you on top, this will depend on how you deploy your application, your provider might do this for you, or you might need to set it up yourself.

/// tip

   open, and any responsibility can be carried by a contributor who demonstrates the required
   capacity and competence.

 * **Be considerate**: People use our work, and we depend on the work of others. Consider users and
   colleagues before taking action. For example, changes to code, infrastructure, policy, and
   documentation may negatively impact others.

///

The only new thing is the `callbacks=invoices_callback_router.routes` as an argument to the *path operation decorator*. We'll see what that is next.

## Documenting the callback

The actual callback code will depend heavily on your own API app.

And it will probably vary a lot from one app to the next.

It could be just one or two lines of code, like:

```Python
callback_url = "https://example.com/api/v1/invoices/events/"

Wenn das Formular stattdessen Dateien enthält, werden diese mit `multipart/form-data` kodiert. Im nächsten Kapitel erfahren Sie mehr über die Handhabung von Dateien.

By this point, it's already clear that **FastAPI** with its ideas is being useful for many people.

It is being chosen over previous alternatives for suiting many use cases better.

Many developers and teams already depend on **FastAPI** for their projects (including me and my team).

But still, there are many improvements and features to come.

**FastAPI** has a great future ahead.

 * violate the {@code Set} contract.
 *
 * <p>The {@code standard} methods and the collection views they return are not guaranteed to be
 * thread-safe, even when all of the methods that they depend on are thread-safe.
 *
 * @author Mike Bostock
 * @author Louis Wasserman
 * @since 2.0
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault

### The Problem

So, what's the problem with installing packages in the global Python environment?

At some point, you will probably end up writing many different programs that depend on **different packages**. And some of these projects you work on will depend on **different versions** of the same package. 😱

a manner which does not create potential liability for other Contributors.
Therefore, if a Contributor includes the Program in a commercial product offering,
such Contributor ("Commercial Contributor") hereby agrees to defend and indemnify
every other Contributor ("Indemnified Contributor") against any losses, damages
and costs (collectively "Losses") arising from claims, lawsuits and other