*       create a "fake" converter for a unit test. It is unnecessary (and confusing) to <i>mock</i>
 *       the {@code Converter} type using a mocking framework.
 *   <li>Pass two lambda expressions or method references to the {@link #from from} factory method.
 *   <li>Extend this class and implement its {@link #doForward} and {@link #doBackward} methods.
 * </ul>
 *
 * <p>Using a converter:
 *

        preauthService.updatePreauthHash(sessionId, "Message2".getBytes());

        byte[] expectedHash = preauthService.getCurrentPreauthHash(sessionId);

        // Validation should pass with correct hash
        assertTrue(preauthService.validatePreauthIntegrity(sessionId, expectedHash));

        // Validation should fail with incorrect hash
        byte[] incorrectHash = new byte[expectedHash.length];

{* ../../docs_src/pydantic_v1_in_v2/tutorial004_an_py310.py hl[4,18] *}

### Migrate in steps { #migrate-in-steps }

/// tip

First try with `bump-pydantic`, if your tests pass and that works, then you're done in one command. ✨

///

    writer.println("rud a chur ar an méar fhada");
    writer.close();

    // First check that we can't find it without setting the context loader.
    // This is a sanity check that the test doesn't spuriously pass because
    // the resource is visible to the system class loader.
    assertThrows(IllegalArgumentException.class, () -> Resources.getResource(tempFile.getName()));

    @Test
    public void test_security_pathTraversalWithLogExtension() {
        // These patterns attempt to access files outside the log directory
        // but must end with .log to pass isLogFilename check

        String sanitized1 = AdminLogAction.sanitizeFilename("../../../var/log/auth.log");
        assertEquals("/var/log/auth.log", sanitized1);

/// note | Technical Details

The other two variables, `image_base64` and `binary_image`, are an image encoded in Base64, and then converted to bytes, to then pass it to `io.BytesIO`.

Only so that it can live in the same file for this example and you can copy it and run it as is. 🥚

///

        if (uncaughtExceptionHandler != null) {
          thread.setUncaughtExceptionHandler(uncaughtExceptionHandler);
        }
        return thread;
      }
    };
  }

  // weird case in which users pass the format string but not the associated arguments
  @SuppressWarnings("AnnotateFormatMethod")
  private static String format(String format, Object... args) {
    return String.format(Locale.ROOT, format, args);
  }

* Ей не нужен реальный код, потому что ваше приложение никогда не будет вызывать эту функцию. Она используется только для документирования *внешнего API*. Поэтому в функции может быть просто `pass`.

        }
    }

    private static List<String> filesFromMerge(String commit) throws IOException, InterruptedException, ExecutionException {
        // Git revision range syntax is part of git, not the shell; pass as-is.
        return getStdoutLines(new String[] {"git", "diff", "--name-only", commit + "^1.." + commit});
    }

Then, in **FastAPI**, you could use a Python class as a dependency.

What FastAPI actually checks is that it is a "callable" (function, class or anything else) and the parameters defined.

If you pass a "callable" as a dependency in **FastAPI**, it will analyze the parameters for that "callable", and process them in the same way as the parameters for a *path operation function*. Including sub-dependencies.