Remember I told you before that `Annotated` can be used to add metadata to your parameters in the [Python Types Intro](../python-types.md#type-hints-with-metadata-annotations){.internal-link target=_blank}?

Now it's the time to use it with FastAPI. 🚀

We had this type annotation:

//// tab | Python 3.10+

```Python
q: str | None = None
```

# Einführung in Python-Typen

Python hat Unterstützung für optionale „Typhinweise“ (Englisch: „Type Hints“). Auch „Typ Annotationen“ genannt.

Diese **„Typhinweise“** oder -Annotationen sind eine spezielle Syntax, die es erlaubt, den <abbr title="Zum Beispiel: str, int, float, bool">Typ</abbr> einer Variablen zu deklarieren.

Durch das Deklarieren von Typen für Ihre Variablen können Editoren und Tools bessere Unterstützung bieten.

   * Get the full set of requirements for a tester class.
   *
   * @param testerMethod a test method of a tester class
   * @return all the constraints implicitly or explicitly required by the method, its declaring
   *     class, or any of its superclasses.
   * @throws ConflictingRequirementsException if the requirements are mutually inconsistent.
   */
  public static TesterRequirements getTesterRequirements(Method testerMethod)

import java.util.Map;
import java.util.Set;
import org.jspecify.annotations.Nullable;

/**
 * A bimap (or "bidirectional map") is a map that preserves the uniqueness of its values as well as
 * that of its keys. This constraint enables bimaps to support an "inverse view", which is another
 * bimap containing the same entries as this bimap but with reversed keys and values.
 *
 * <h3>Implementations</h3>
 *

Use its [builder][handshake_certificates_builder] to define which certificates the HTTPS server
returns to its clients. The returned instance can create an `SSLSocketFactory` that implements this
policy:

```java
HandshakeCertificates serverCertificates = new HandshakeCertificates.Builder()
    .heldCertificate(localhostCertificate)
    .build();
MockWebServer server = new MockWebServer();

        uses: actions/cache@0400d5f644dc74513175e3cd8d07132dd4860809 # v4
        with:
          path: ~/.mimir/local
          key: mimir-${{ runner.os }}-its-${{ hashFiles('**/pom.xml') }}
          restore-keys: |
            mimir-${{ runner.os }}-its-
            mimir-${{ runner.os }}-

      - name: Download Maven distribution
        uses: actions/download-artifact@634f93cb2916e3fdff6788551b99b062d0335ce0 # v4

         Module Metadata hides the dependency declared in `guava` from runtime
         configurations downstream, and GWT uses the runtime configuration for
         its builds. Thus, GWT doesn't get j2objc-annotations transitively, in
         contrast to the other deps of `guava`, which it does get transitively.
         (Arguably we should redeclare *all* the `guava` deps here.) -->
    <dependency>

		header.Set("X-Content-Type-Options", "nosniff")                                // Prevent mime-sniff
		header.Set("Strict-Transport-Security", "max-age=31536000; includeSubDomains") // HSTS mitigates variants of MITM attacks

		// Previously, this value was set right before a response was sent to
		// the client. So, logger and Error response XML were not using this

		t.Fatalf("Creating a volume failed with %s expected to pass.", err)
	}

	// Stat to get permissions bits.
	st, err := os.Stat(path.Join(tmpPath, testCase.volName))
	if err != nil {
		t.Fatalf("Stat failed with %s expected to pass.", err)
	}

	// Get umask of the bits stored.
	currentUmask := 0o777 - uint32(st.Mode().Perm())

	// Verify if umask is correct.

          source.readData(data)
        }

        in 5..7 -> {
          data.writeByte('\n'.code) // 'data' on a line of its own.
        }

        in 8..9 -> {
          id = source.readUtf8LineStrict().takeIf { it.isNotEmpty() }
        }

        in 10..12 -> {
          id = null // 'id' on a line of its own.
        }

        in 13..14 -> {
          type = source.readUtf8LineStrict().takeIf { it.isNotEmpty() }