public static final String ALL_LANGUAGES = "all";

    public static final String INVALID_NUMERIC_PARAMETER = "-1";

    public static final String FACET_FIELD_PREFIX = "field:";

    public static final String FACET_QUERY_PREFIX = "query:";

    public static final String MATCHES_ALL_QUERY = "*:*";

    @Deprecated

     * the encoded path will have a trailing '/'.
     *
     * Popping "/a/b/c/" yields "/a/b/". In this case the list of path segments goes from ["a",
     * "b", "c", ""] to ["a", "b", ""].
     *
     * Popping "/a/b/c" also yields "/a/b/". The list of path segments goes from ["a", "b", "c"]
     * to ["a", "b", ""].
     */
    private fun pop() {

	if errCode != ErrUnsignedHeaders {
		t.Fatalf("Expected the APIErrorCode to %d, but got %d", ErrUnsignedHeaders, errCode)
	}

	// case where the list of signed headers doesn't contain the host field.
	signedHeaders = signedHeaders[2:5]
	// expected to fail with `ErrUnsignedHeaders`.
	_, errCode = extractSignedHeaders(signedHeaders, r)
	if errCode != ErrUnsignedHeaders {

You can use all the same validation features and tools you use for Pydantic models, like different data types and additional validations with `Field()`.

//// tab | Pydantic v2

```Python hl_lines="2  5-8  11"
{!> ../../docs_src/settings/tutorial001.py!}
```

////

//// tab | Pydantic v1

/// info

type validator struct{}

func checkFields(un *unstructured.Unstructured) error {
	var errs error
	for key := range un.Object {
		if _, ok := validFields[key]; !ok {
			errs = multierror.Append(errs, fmt.Errorf("unknown field %q", key))
		}
	}
	return errs
}

func (v *validator) validateResource(istioNamespace, defaultNamespace string, un *unstructured.Unstructured, writer io.Writer) (validation.Warning, error) {

🗄 `BaseSettings` ⚪️➡️ Pydantic & ✍ 🎧-🎓, 📶 🌅 💖 ⏮️ Pydantic 🏷.

🎏 🌌 ⏮️ Pydantic 🏷, 👆 📣 🎓 🔢 ⏮️ 🆎 ✍, & 🎲 🔢 💲.

👆 💪 ⚙️ 🌐 🎏 🔬 ⚒ & 🧰 👆 ⚙️ Pydantic 🏷, 💖 🎏 📊 🆎 & 🌖 🔬 ⏮️ `Field()`.

```Python hl_lines="2  5-8  11"
{!../../docs_src/settings/tutorial001.py!}
```

/// tip

🚥 👆 💚 🕳 ⏩ 📁 & 📋, 🚫 ⚙️ 👉 🖼, ⚙️ 🏁 1️⃣ 🔛.

///

        throw new IllegalArgumentException("Trailing high surrogate at end of input");
      }
      // It is possible for this to return null because nextEscapeIndex() may
      // (for performance reasons) yield some false positives but it must never
      // give false negatives.
      char[] escaped = escape(cp);
      int nextIndex = index + (Character.isSupplementaryCodePoint(cp) ? 2 : 1);
      if (escaped != null) {

   * Returns a big-endian representation of {@code value} in an 8-element byte array; equivalent to
   * {@code ByteBuffer.allocate(8).putLong(value).array()}. For example, the input value {@code
   * 0x1213141516171819L} would yield the byte array {@code {0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
   * 0x18, 0x19}}.
   *
   * <p>If you need to convert and concatenate several values (possibly even of different types),

  /** The parts of the domain name, converted to lower case. */
  private final ImmutableList<String> parts;

  /**
   * Cached value of #publicSuffixIndex(). Do not use directly.
   *
   * <p>Since this field isn't {@code volatile}, if an instance of this class is shared across
   * threads before it is initialized, then each thread is likely to compute their own copy of the
   * value.
   */
  @SuppressWarnings("Immutable")

   * Returns a big-endian representation of {@code value} in an 8-element byte array; equivalent to
   * {@code ByteBuffer.allocate(8).putLong(value).array()}. For example, the input value {@code
   * 0x1213141516171819L} would yield the byte array {@code {0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
   * 0x18, 0x19}}.
   *
   * <p>If you need to convert and concatenate several values (possibly even of different types),