The process that happens when your API app calls the *external API* is named a "callback". Because the software that the external developer wrote sends a request to your API and then your API *calls back*, sending a request to an *external API* (that was probably created by the same developer).

Ich denke, `Union[SomeType, None]` ist expliziter bezüglich seiner Bedeutung.

Es geht nur um Wörter und Namen. Aber diese Worte können beeinflussen, wie Sie und Ihre Teamkollegen über den Code denken.

Nehmen wir zum Beispiel diese Funktion:

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

		t.Errorf("w.Flush() = %v, want nil", err)
	}

	if got, want := rfw.writeBytes, bufsize; got != want {
		t.Errorf("wrote %v bytes with Write, want %v", got, want)
	}
	if got, want := rfw.readFromBytes, len(input)-bufsize; got != want {
		t.Errorf("wrote %v bytes with ReadFrom, want %v", got, want)
	}
}

func TestReadZero(t *testing.T) {
	for _, size := range []int{100, 2} {

	// Call the ServeHTTP to execute the handler.
	apiRouter.ServeHTTP(rec, req)

	ctx, cancel := context.WithCancel(GlobalContext)
	defer cancel()

	// Now check if we actually wrote to backend (regardless of the response
	// returned by the server).
	z := obj.(*erasureServerPools)
	xl := z.serverPools[0].sets[0]
	erasureDisks := xl.getDisks()

	fmt.Println(missing, "bytes missing. Truncating", len(filled)-lastValid-1, "from end.")
	mapped = mapped[:lastValid+1]
	err := os.WriteFile(out, mapped, os.ModePerm)
	if err != nil {
		return err
	}
	fmt.Println("Wrote output to", out)
	return nil

	}
	for len(p) > 0 {
		n := copy(ss.buf[ss.start:], p)
		p = p[n:]
		ss.start += n
		if ss.start == ss.keep {
			ss.start = 0
		}
	}
	return
}

// generatesZip64 reports whether f wrote a zip64 file.
// f is also responsible for closing w.
func generatesZip64(t *testing.T, f func(w *Writer)) bool {
	ss := &suffixSaver{keep: 10 << 20}
	w := NewWriter(ss)
	f(w)
	return suffixIsZip64(t, ss)
}

				Name:     "readonly",
				Content:  []byte("important \r\n"),
				Modified: time.Date(2011, 12, 8, 10, 6, 8, 0, timeZone(0)),
				Mode:     0444,
			},
		},
	},
	{
		// created by Go, before we wrote the "optional" data
		// descriptor signatures (which are required by macOS).
		// Use obscured file to avoid Apple’s notarization service
		// rejecting the toolchain due to an inability to unzip this archive.

	// Call the ServeHTTP to execute the handler.
	apiRouter.ServeHTTP(rec, req)

	ctx, cancel := context.WithCancel(GlobalContext)
	defer cancel()

	// Now check if we actually wrote to backend (regardless of the response
	// returned by the server).
	z := obj.(*erasureServerPools)
	xl := z.serverPools[0].sets[0]
	erasureDisks := xl.getDisks()

## Version 4.0.0

_2019-06-26_

**This release upgrades OkHttp to Kotlin.** We tried our best to make fast and safe to upgrade
from OkHttp 3.x. We wrote an [upgrade guide][upgrading_to_okhttp_4] to help with the migration and a
[blog post][okhttp4_blog_post] to explain it.

 *  Fix: Target Java 8 bytecode for Java and Kotlin.


## Version 4.0.0-RC3

on the Library, the distribution of the whole must be on the terms of
this License, whose permissions for other licensees extend to the
entire whole, and thus to each and every part regardless of who wrote
it.

Thus, it is not the intent of this section to claim rights or contest
your rights to work written entirely by you; rather, the intent is to
exercise the right to control the distribution of derivative or