## Pydantic Modelle

<a href="https://pydantic-docs.helpmanual.io/" class="external-link" target="_blank">Pydantic</a> ist eine Python-Bibliothek für die Validierung von Daten.

Sie deklarieren die „Form“ der Daten als Klassen mit Attributen.

Und jedes Attribut hat einen Typ.

			for _, rl := range lcCfg.Rules {
				if !rl.Expiration.IsNull() || !rl.NoncurrentVersionExpiration.IsNull() {
					expiryRuleRemoved = true
					break
				}
			}
		}

		// Form empty ILM details with `ExpiryUpdatedAt` field and save
		var cfgData []byte
		if expiryRuleRemoved {
			var lcCfg lifecycle.Lifecycle
			currtime := time.Now()
			lcCfg.ExpiryUpdatedAt = &currtime

		HTTPStatusCode: http.StatusRequestedRangeNotSatisfiable,
	},
	ErrInvalidPolicyDocument: {
		Code:           "InvalidPolicyDocument",
		Description:    "The content of the form does not meet the conditions specified in the policy document.",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrAccessDenied: {
		Code:           "AccessDenied",
		Description:    "Access Denied.",

  // For example, the reference to the expression of the first item of
  // validations is "spec.validations[0].expression"
  optional string fieldRef = 2;

  // The content of type checking information in a human-readable form.
  // Each line of the warning contains the type that the expression is checked
  // against, followed by the type check error from the compiler.
  optional string warning = 3;
}

message MatchCondition {

		// and also skip traces with function name that starts with "runtime."
		if !strings.HasPrefix(file, "<autogenerated>") &&
			!strings.HasPrefix(funcName, "runtime.") {
			// Form and append a line of stack trace into a
			// collection, 'trace', to build full stack trace
			trace = append(trace, fmt.Sprintf("%v:%v:%v()", file, lineNumber, funcName))

You can also return Pydantic models (you'll see more about that later).

There are many other objects and models that will be automatically converted to JSON (including ORMs, etc). Try using your favorite ones, it's highly probable that they are already supported.

## Recap

* Import `FastAPI`.
* Create an `app` instance.

```Python hl_lines="3  5"
{!../../docs_src/dependencies/tutorial007.py!}
```

## Unterabhängigkeiten mit `yield`.

Sie können Unterabhängigkeiten und „Bäume“ von Unterabhängigkeiten beliebiger Größe und Form haben, und einige oder alle davon können `yield` verwenden.

**FastAPI** stellt sicher, dass der „Exit-Code“ in jeder Abhängigkeit mit `yield` in der richtigen Reihenfolge ausgeführt wird.

			if r1 == utf8.RuneError {
				return i
			}
			i += n
		}
		return -1
	case !utf8.ValidRune(r):
		return -1
	default:
		// Search for rune r using the last byte of its UTF-8 encoded form.
		// The distribution of the last byte is more uniform compared to the
		// first byte which has a 78% chance of being [240, 243, 244].
		var b [utf8.UTFMax]byte
		n := utf8.EncodeRune(b[:], r)
		last := n - 1

,n.always(function(){void 0===i?ce(ie).removeProp(r):ie[r]=i,e[r]&&(e.jsonpCallback=t.jsonpCallback,Kt.push(r)),o&&v(i)&&i(o[0]),o=i=void 0}),"script"}),le.createHTMLDocument=((Jt=C.implementation.createHTMLDocument("").body).innerHTML="<form></form><form></form>",2===Jt.childNodes.length),ce.parseHTML=function(e,t,n){return"string"!=typeof e?[]:("boolean"==typeof t&&(n=t,t=!1),t||(le.createHTMLDocument?((r=(t=C.implementation.createHTMLDocument("")).createElement("base")).href=C.location.href,t...

				"application/vnd.shana.informed.package",
				"application/vnd.simtech-mindmapper",
				"application/vnd.smaf",
				"application/vnd.smart.teacher",
				"application/vnd.software602.filler.form+xml",
				"application/vnd.software602.filler.form-xml-zip",
				"application/vnd.solent.sdkm+xml",
				"application/vnd.spotfire.dxp",
				"application/vnd.spotfire.sfs",
				"application/vnd.sss-cod",
				"application/vnd.sss-dtf",