"""
        if self.cid is not None:
            fetcher = self._create_credentials_fetcher()
            return RefreshableCredentials.create_from_metadata(
                metadata=fetcher(),
                refresh_using=fetcher,
                method=self.METHOD,
            )
        else:
            return None

    def _create_credentials_fetcher(self):
        method = self.METHOD

import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

/**
 * The {@code Immutable} annotation indicates that the object is immutable, i.e.
 * none of its field can be changed.  This also ensures that the type is
 * {@link ThreadSafe}.
 *
 * @see ThreadSafe
 * @since 4.0.0
 */
@Experimental
@Documented
@Retention(RetentionPolicy.CLASS)
@ThreadSafe

    #   NONE - Do nothing. (default)
    #   EXCEPTION - It throws an exception.
    #   RFILL - It fills the parameter by right spaces.
    #   LFILL - It fills the parameter by left spaces.
    #
    #; shortCharHandlingMode = NONE
    # - - - - - - - - - -/

    # /- - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
    # o quoteTableNameList: (NotRequired - Default list:{})

     */
    void setRepository(ArtifactRepository remoteRepository);

    /**
     * Get the repository metadata associated with this marker.
     *
     * @return the metadata, or <code>null</code> if none loaded
     */
    Metadata getMetadata();

    /**
     * Set the metadata contents.
     *
     * @param metadata the metadata
     */
    void setMetadata(Metadata metadata);

    /**

  </parent>

  <artifactId>maven-api-di</artifactId>
  <name>Maven 4 API :: Dependency Injection</name>
  <description>Maven 4 API - Dependency Injection</description>

  <properties>
    <maven.compiler.proc>none</maven.compiler.proc>
  </properties>

 */
@Experimental
@Immutable
public enum DependencyScope {

    /**
     * None. Allows you to declare dependencies (for example to alter reactor build order) but in reality dependencies
     * in this scope are not part of any path scope.
     */
    NONE("none", false),

    /**
     * Undefined. When no scope is explicitly given, UNDEFINED will be used, but its meaning will depend on

-->

#### What type of PR is this?

<!--
Add one of the following kinds:
/kind bug
/kind cleanup
/kind documentation
/kind feature

Optionally add one or more of the following kinds if applicable:
/kind api-change
/kind deprecation
/kind failing-test
/kind flake
/kind regression
-->

app = FastAPI()


class Item(BaseModel):
    name: str
    price: float
    is_offer: Union[bool, None] = None


@app.get("/")
def read_root():
    return {"Hello": "World"}


@app.get("/items/{item_id}")
def read_item(item_id: int, q: Union[str, None] = None):
    return {"item_id": item_id, "q": q}


@app.put("/items/{item_id}")
def update_item(item_id: int, item: Item):

     * @return the classifier or an empty string if none, never {@code null}
     * @see ArtifactCoordinates#getClassifier()
     */
    @Nonnull
    String getClassifier();

    /**
     * Returns the file extension of the artifact.
     * The dot separator is not included in the returned string.
     *
     * @return the file extension or an empty string if none, never {@code null}

     * {@return the identifier of the artifact}.
     */
    @Nonnull
    String getArtifactId();

    /**
     * Returns the classifier of the artifact.
     *
     * @return the classifier or an empty string if none, never {@code null}
     */
    @Nonnull
    String getClassifier();

    /**
     * {@return the specific version, range of versions, or meta-version of the artifact}.