* Read other ideas, articles, and read about tools I have created.
    * Follow me to read when I publish something new.

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

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

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

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

  // More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#metadata
  // +optional
  optional k8s.io.apimachinery.pkg.apis.meta.v1.ObjectMeta metadata = 1;

  // Spec holds information about the request being evaluated.  spec.namespace must be equal to the namespace
  // you made the request against.  If empty, it is defaulted.
  optional SubjectAccessReviewSpec spec = 2;

    * That's one layer **below HTTP**.
    * So, the **certificate and encryption** handling is done **before HTTP**.
* **TCP doesn't know about "domains"**. Only about IP addresses.
    * The information about the **specific domain** requested goes in the **HTTP data**.
* The **HTTPS certificates** "certify" a **certain domain**, but the protocol and encryption happen at the TCP level, **before knowing** which domain is being dealt with.

  // More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#metadata
  // +optional
  optional k8s.io.apimachinery.pkg.apis.meta.v1.ObjectMeta metadata = 1;

  // Spec holds information about the request being evaluated.  spec.namespace must be equal to the namespace
  // you made the request against.  If empty, it is defaulted.
  optional SubjectAccessReviewSpec spec = 2;

I think `Union[SomeType, None]` is more explicit about what it means.

It's just about the words and names. But those words can affect how you and your teammates think about the code.

As an example, let's take this function:

```Python hl_lines="1  4"
{!../../../docs_src/python_types/tutorial009c.py!}
```

	configCmd := &cobra.Command{
		Use:   "proxy-config",
		Short: "Retrieve information about proxy configuration from Envoy [kube only]",
		Long:  `A group of commands used to retrieve information about proxy configuration from the Envoy config dump`,
		Example: `  # Retrieve information about proxy configuration from an Envoy instance.

 *   <li>element extraction methods which facilitate the retrieval of certain elements (for example
 *       {@link #last})
 *   <li>query methods which answer questions about the {@code FluentIterable}'s contents (for
 *       example {@link #anyMatch})
 *   <li>conversion methods which copy the {@code FluentIterable}'s contents into a new collection
 *       or array (for example {@link #toList})

    collected using form data (instead of JSON) and that it should have the specific
    fields `username` and `password`.

    All the initialization parameters are extracted from the request.

    Read more about it in the
    [FastAPI docs for Simple OAuth2 with Password and Bearer](https://fastapi.tiangolo.com/tutorial/security/simple-oauth2/).

    ## Example

    ```python
    from typing import Annotated