This is particularly useful when automatically generating clients or
                SDKs for your API.

                Read more about it in the
                [FastAPI docs about how to Generate Clients](https://fastapi.tiangolo.com/advanced/generate-clients/#custom-generate-unique-id-function).
                """
            ),
        ] = Default(generate_unique_id),

		Long:  "A group of commands used to update or retrieve Ztunnel configuration from a Ztunnel instance.",
		Example: `  # Retrieve summary about workload configuration
  istioctl ztunnel-config workload

  # Retrieve summary about certificates
  istioctl ztunnel-config certificates`,
		Aliases: []string{"zc"},
	}

	configCmd.AddCommand(logCmd(ctx))
	configCmd.AddCommand(workloadConfigCmd(ctx))

Here's a small preview of how you could integrate Strawberry with FastAPI:

{* ../../docs_src/graphql/tutorial001.py hl[3,22,25:26] *}

You can learn more about Strawberry in the <a href="https://strawberry.rocks/" class="external-link" target="_blank">Strawberry documentation</a>.

And also the docs about <a href="https://strawberry.rocks/docs/integrations/fastapi" class="external-link" target="_blank">Strawberry with FastAPI</a>.

///

## Type Hints with Metadata Annotations

## About Starlette

You shouldn't pin the version of `starlette`.

Different versions of **FastAPI** will use a specific newer version of Starlette.

So, you can just let **FastAPI** use the correct Starlette version.

## About Pydantic

		Short: "Retrieves cluster configuration for the Envoy in the specified pod",
		Long:  `Retrieve information about cluster configuration for the Envoy instance in the specified pod.`,
		Example: `  # Retrieve summary about cluster configuration for a given pod from Envoy.
  istioctl proxy-config clusters <pod-name[.namespace]>

  # Retrieve summary about cluster configuration for a pod under a deployment from Envoy.

```

</div>

////

This information will be useful when learning about [Virtual Environments](virtual-environments.md){.internal-link target=_blank}.

## Conclusion

With this you should have a basic understanding of what **environment variables** are and how to use them in Python.

I'll show you some concrete examples in the next chapters.

---

Then the next concepts to consider are all about the program running your actual API (e.g. Uvicorn).

## Program and Process

We will talk a lot about the running "**process**", so it's useful to have clarity about what it means, and what's the difference with the word "**program**".

### What is a Program

 * that exhibits the problem.
 *
 */
public interface Problem {

    /**
     * The different severity levels for a problem, in decreasing order.
     */
    enum Severity {
        FATAL, //
        ERROR, //
        WARNING //
    }

    /**

As you saw in the previous chapter about [Deployment Concepts](concepts.md){.internal-link target=_blank}, there are multiple strategies you can use.

Here I'll show you how to use **Uvicorn** with **worker processes** using the `fastapi` command or the `uvicorn` command directly.

/// info