if value is None:
        if field.required:
            return None, [get_missing_field_error(loc=loc)]
        else:
            return deepcopy(field.default), []
    v_, errors_ = field.validate(value, values, loc=loc)
    if isinstance(errors_, list):
        new_errors = _regenerate_error_with_loc(errors=errors_, loc_prefix=())
        return None, new_errors
    else:
        return v_, []

Cada atributo de um modelo Pydantic tem um tipo.

Mas esse tipo pode ser outro modelo Pydantic.

Portanto, você pode declarar "objects" JSON profundamente aninhados com nomes, tipos e validações de atributos específicos.

Tudo isso, aninhado arbitrariamente.

### Defina um sub-modelo { #define-a-submodel }

Por exemplo, nós podemos definir um modelo `Image`:

long maxAccessCount = 0         // Max URLs (0 = unlimited)
```

### CrawlerThread (`CrawlerThread.java`)

Worker thread for crawling.

**Flow**: Poll URL → Validate → Get client → Delay → Check last-modified → Execute → Process → Extract children → Queue children → Delay

### CrawlerClientFactory

Pattern-based client selection using `LinkedHashMap<Pattern, CrawlerClient>`.

        // Directory leasing requires SMB 3.0 or higher
        // MS-SMB2: Level 2 leasing (which includes directory leasing) is only supported in SMB 3.0+
        // We'll validate this when we actually need to use the session

        // Request base lease
        Smb2LeaseKey leaseKey = baseLeaseManager.requestLease(directoryPath, requestedState);

        // Create directory cache entry

            assertFalse(UniAddress.isDotQuadIP(input));
        }

        @Test
        void shouldReturnTrueForInvalidOctetValues() {
            // isDotQuadIP does not validate octet values, only checks format
            assertTrue(UniAddress.isDotQuadIP("192.168.1.256"));
            assertTrue(UniAddress.isDotQuadIP("999.999.999.999"));
        }

        @Test

//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

// Package cmd This file implements helper functions to validate AWS
// Signature Version '4' authorization header.
//
// This package provides comprehensive helpers for following signature
// types.
// - Based on Authorization header.
// - Based on Query parameters.

Когда вы устанавливаете FastAPI с помощью `pip install "fastapi[standard]"`, он идёт с группой опциональных зависимостей `standard`:

Используется Pydantic:

* <a href="https://github.com/JoshData/python-email-validator" target="_blank"><code>email-validator</code></a> — для проверки адресов электронной почты.

Используется Starlette:

## Opsiyonel Gereksinimler

Pydantic tarafında kullanılan:

* <a href="https://github.com/JoshData/python-email-validator" target="_blank"><code>email-validator</code></a> - email doğrulaması için.
* <a href="https://docs.pydantic.dev/latest/usage/pydantic_settings/" target="_blank"><code>pydantic-settings</code></a> - ayar yönetimi için.

            }

            // SECURITY WARNING: JWT signature validation is not implemented.
            // This is a critical security vulnerability. The ID token should be validated
            // to ensure it was issued by the expected OpenID Connect provider and has not been tampered with.
            // TODO: Implement JWT signature validation using the provider's public key

It can't handle nested models very well. So, if the JSON body in the request is a JSON object that has inner fields that in turn are nested JSON objects, it cannot be properly documented and validated.

/// check | Inspired **FastAPI** to

Use Python types to have great editor support.

Have a powerful dependency injection system. Find a way to minimize code repetition.

///