* <li>{@code classDocbookDir} - A directory that should contain docbook template for each class referenced in main docbook template.</li>
 * </ul>
 *
 * Produces the following:
 * <ul>
 * <li>A docbook book XML file containing the reference.</li>
 * <li>A meta-data file containing information about where the canonical documentation for each class can be found:
 * as dsl doc, javadoc or groovydoc.</li>
 * </ul>
 */
@CacheableTask

from fastapi import FastAPI, Path
from pydantic import BaseModel

app = FastAPI()


class Item(BaseModel):
    name: str
    description: str | None = None
    price: float
    tax: float | None = None


@app.put("/items/{item_id}")
async def update_item(
    *,
    item_id: int = Path(title="The ID of the item to get", ge=0, le=1000),
    q: str | None = None,
    item: Item | None = None,
):

    public ValueSetLink<K, V> getPredecessorInValueSet() {
      return requireNonNull(predecessorInValueSet); // see the comment on the class fields
    }

    @Override
    public ValueSetLink<K, V> getSuccessorInValueSet() {
      return requireNonNull(successorInValueSet); // see the comment on the class fields
    }

    @Override
    public void setPredecessorInValueSet(ValueSetLink<K, V> entry) {

<img src="/img/python-types/image06.png">

Notice that this means "`one_person` is an **instance** of the class `Person`".

It doesn't mean "`one_person` is the **class** called `Person`".

## Pydantic models

<a href="https://docs.pydantic.dev/" class="external-link" target="_blank">Pydantic</a> is a Python library to perform data validation.

/**
 * An enhanced {@link ObjectWithFieldsConverter} leveraging the {@link TypeAwareExpressionEvaluator}
 * interface.
 */
class EnhancedConfigurationConverter extends ObjectWithFieldsConverter {
    protected Object fromExpression(
            final PlexusConfiguration configuration, final ExpressionEvaluator evaluator, final Class<?> type)
            throws ComponentConfigurationException {
        String value = configuration.getValue();
        try {

@SuppressWarnings("JUnit4ClassUsedInJUnit3")
public class MultisetAddTester<E> extends AbstractMultisetTester<E> {
  @CollectionFeature.Require(absent = SUPPORTS_ADD)
  public void testAddUnsupported() {
    assertThrows(UnsupportedOperationException.class, () -> getMultiset().add(e0()));
  }

  @CollectionFeature.Require(SUPPORTS_ADD)
  public void testAddMeansAddOne() {

      Class<? super @NonNull E> type, E... contents) {
    return new MinimalCollection<>(type, true, contents);
  }

  private final E[] contents;
  private final Class<? super @NonNull E> type;
  private final boolean allowNulls;

  // Package-private so that it can be extended.
  MinimalCollection(Class<? super @NonNull E> type, boolean allowNulls, E... contents) {

      .build();
  private final Moshi moshi = new Moshi.Builder().build();
  private final JsonAdapter<Map<String, String>> mapJsonAdapter = moshi.adapter(
      Types.newParameterizedType(Map.class, String.class, String.class));

  public void run() throws Exception {
    Map<String, String> requestBody = new LinkedHashMap<>();
    requestBody.put("longUrl", "https://publicobject.com/2014/12/04/html-formatting-javadocs/");

    TestHasher hasher = new TestHasher();
    assertThrows(IndexOutOfBoundsException.class, () -> hasher.putBytes(new byte[8], -1, 4));
    assertThrows(IndexOutOfBoundsException.class, () -> hasher.putBytes(new byte[8], 0, 16));
    assertThrows(IndexOutOfBoundsException.class, () -> hasher.putBytes(new byte[8], 0, -1));
  }

  private class TestHasher extends AbstractByteHasher {

  // value represents the integer value of this priority class. This is the actual priority that pods
  // receive when they have the name of this class in their pod spec.
  optional int32 value = 2;

  // globalDefault specifies whether this PriorityClass should be considered as
  // the default priority for pods that do not have any priority class.
  // Only one PriorityClass can be marked as `globalDefault`. However, if more than