// are responsible for serializing and deserializing the objects that contain
// their internal state.
// Once a ControllerRevision has been successfully created, it can not be updated.
// The API Server will fail validation of all requests that attempt to mutate
// the Data field. ControllerRevisions may, however, be deleted. Note that, due to its use by both

A `FastAPI` application (instance) has an `.openapi()` method that is expected to return the OpenAPI schema.

As part of the application object creation, a *path operation* for `/openapi.json` (or for whatever you set your `openapi_url`) is registered.

It just returns a JSON response with the result of the application's `.openapi()` method.

Now create Pydantic *models* (schemas) that will be used when reading data, when returning it from the API.

For example, before creating an item, we don't know what will be the ID assigned to it, but when reading it (when returning it from the API) we will already know its ID.

The same way, when reading a user, we can now declare that `items` will contain the items that belong to this user.

`secrets.compare_digest()` needs to take `bytes` or a `str` that only contains ASCII characters (the ones in English), this means it wouldn't work with characters like `á`, as in `Sebastián`.

To handle that, we first convert the `username` and `password` to `bytes` encoding them with UTF-8.

Then we can use `secrets.compare_digest()` to ensure that `credentials.username` is `"stanleyjobson"`, and that `credentials.password` is `"swordfish"`.

=== "Python 3.9+"

			for _, sz := range test.sizes {
				h.add(sz)
			}
			got := h.toMap()
			exp := test.want
			// what is in exp is in got
			for k := range exp {
				if exp[k] != got[k] {
					t.Fatalf("interval %s: Expected %d values but got %d values\n", k, exp[k], got[k])
				}
			}
			// what is absent in exp is absent in got too
			for k := range got {
				if _, ok := exp[k]; !ok && got[k] > 0 {

            return false;
        }

        MavenProject that = (MavenProject) other;

        return Objects.equals(getArtifactId(), that.getArtifactId())
                && Objects.equals(getGroupId(), that.getGroupId())
                && Objects.equals(getVersion(), that.getVersion());
    }

    @Override
    public int hashCode() {

It is not encrypted, so, anyone could recover the information from the contents.

But it's signed. So, when you receive a token that you emitted, you can verify that you actually emitted it.

That way, you can create a token with an expiration of, let's say, 1 week. And then when the user comes back the next day with the token, you know that user is still logged in to your system.

    ```

## Request body + path parameters

You can declare path parameters and request body at the same time.

**FastAPI** will recognize that the function parameters that match path parameters should be **taken from the path**, and that function parameters that are declared to be Pydantic models should be **taken from the request body**.

=== "Python 3.10+"

    ```Python hl_lines="15-16"

// all leading UTF-8-encoded code points c that satisfy f(c).
func TrimLeftFunc(s []byte, f func(r rune) bool) []byte {
	i := indexFunc(s, f, false)
	if i == -1 {
		return nil
	}
	return s[i:]
}

// TrimRightFunc returns a subslice of s by slicing off all trailing
// UTF-8-encoded code points c that satisfy f(c).
func TrimRightFunc(s []byte, f func(r rune) bool) []byte {

If you plan to write assembly language, you should read that document although much of it is Plan 9-specific.
The current document provides a summary of the syntax and the differences with
what is explained in that document, and
describes the peculiarities that apply when writing assembly code to interact with Go.
</p>

<p>
The most important thing to know about Go's assembler is that it is not a direct representation of the underlying machine.