* </p>
     */
    @Test
    void testJdk7ipv6() {
        ConnectException connEx = new ConnectException("Connection refused: connect");
        IOException ioEx = new IOException("Unable to establish loopback connection", connEx);
        MojoExecutionException mojoEx =
                new MojoExecutionException("Error executing Jetty: Unable to establish loopback connection", ioEx);

    assertEquals((Integer) 1, converter.convert("one"));
    assertEquals((Integer) 2, converter.convert("two"));
    assertThrows(IllegalArgumentException.class, () -> converter.convert("three"));

    biMap.put("three", 3);

    assertEquals((Integer) 1, converter.convert("one"));
    assertEquals((Integer) 2, converter.convert("two"));
    assertEquals((Integer) 3, converter.convert("three"));
  }

 * possible readings.
 * </p>
 *
 * <p>
 * The class also utilizes ICU4J's {@link com.ibm.icu.text.Transliterator} to convert full-width characters
 * to half-width and to convert any characters to lowercase, ensuring consistency in the output.
 * </p>
 *
 * <p>
 * Example:
 * For the input "キャ", the converter might return a list containing "kya".

    # Vocabularies for Semantic Content With "format"
    format: Optional[str] = None
    # Ref: JSON Schema Validation 2020-12: https://json-schema.org/draft/2020-12/json-schema-validation.html#name-a-vocabulary-for-the-conten
    # A Vocabulary for the Contents of String-Encoded Data
    contentEncoding: Optional[str] = None
    contentMediaType: Optional[str] = None
    contentSchema: Optional["SchemaOrBool"] = None

				a.setInt(iA)
			} else if fA, ok := a.bytesToFloat(); ok {
				a.setFloat(fA)
			} else {
				return fmt.Errorf("Could not convert %s to a number", a.String())
			}

		case bool:
			if bA, ok := a.bytesToBool(); ok {
				a.setBool(bA)
			} else {
				return fmt.Errorf("Could not convert %s to a boolean", a.String())
			}

		default:
			return errCmpMismatchedTypes
		}
		return nil

    /**
     * Default constructor.
     */
    public PrefixQueryCommand() {
        super();
    }

    private static final Logger logger = LogManager.getLogger(PrefixQueryCommand.class);

    /** Flag to convert wildcard to lowercase. */
    protected boolean lowercaseWildcard = true;

    @Override
    protected String getQueryClassName() {
        return PrefixQuery.class.getSimpleName();
    }

    @Override

        return childUrlRuleMap.entrySet().stream().map(e -> new Pair<>(e.getKey(), e.getValue()));
    }

    /**
     * Converts child URLs using the URL convert helper.
     *
     * @param requestDataList the list of request data to convert
     * @return the converted list of request data
     */
    protected List<RequestData> convertChildUrlList(final List<RequestData> requestDataList) {
        try {

  @CanIgnoreReturnValue
  public CharEscaperBuilder addEscapes(char[] cs, String r) {
    checkNotNull(r);
    for (char c : cs) {
      addEscape(c, r);
    }
    return this;
  }

  /**
   * Convert this builder into an array of char[]s where the maximum index is the value of the
   * highest character that has been seen. The array will be sparse in the sense that any unseen
   * index will default to null.
   *

@callback_router.get(
    "{$callback_url}/callback/", responses={400: {"model": CustomModel}}
)
def callback_route():
    pass  # pragma: no cover


@app.post("/", callbacks=callback_router.routes)
def main_route(callback_url: HttpUrl):
    pass  # pragma: no cover


client = TestClient(app)


def test_openapi_schema():
    response = client.get("/openapi.json")

So, even with the code above that doesn't use Pydantic explicitly, FastAPI is using Pydantic to convert those standard dataclasses to Pydantic's own flavor of dataclasses.

And of course, it supports the same:

* data validation
* data serialization
* data documentation, etc.