checkHelperVersion(NO_UNSAFE, "AtomicReferenceFieldUpdaterAtomicHelper");
    checkHelperVersion(NO_ATOMIC_REFERENCE_FIELD_UPDATER, "SynchronizedHelper");

    // Then, run the actual tests under each alternative classloader:

    /*
     * Under Java 8, there is no need to test the no-VarHandle case here: It's already tested by the
     * main AbstractFutureTest, which uses the default AtomicHelper, which we verified above to be

It is imported/included directly into FastAPI so that you can import it from `fastapi` and avoid accidentally importing the alternative `BackgroundTask` (without the `s` at the end) from `starlette.background`.

     * below, we actually run the AbstractFutureTest methods under that scenario.
     */
    checkHelperVersion(NO_ATOMIC_REFERENCE_FIELD_UPDATER, "SynchronizedHelper");

    // Then, run the actual tests under each alternative classloader:

    /*
     * We don't need to test further under NO_UNSAFE: We verified that it selects
     * AtomicReferenceFieldUpdaterAtomicHelper, which is the default, which means that it's used

    builder.setUnsafeReplacement("\uFFFD");

    /*
     * Except for \n, \t, and \r, all ASCII control characters are replaced with the Unicode
     * replacement character.
     *
     * Implementation note: An alternative to the following would be to make a map that simply
     * replaces the allowed ASCII whitespace characters with themselves and to set the minimum safe

            try {
                ChannelInfo alternativeChannel = manager.getLoadBalancer().selectChannel(op);
                alternativeChannel.addPendingOperation(op);
                // Operation would be resent on alternative channel
                // For now, skip actual send implementation
            } catch (Exception e) {
                log.error("Failed to redistribute operation", e);

 *
 * To perform server authentication:
 *
 *  * The server's handshake certificates must have a [held certificate][HeldCertificate] (a
 *    certificate and its private key). The certificate's subject alternative names must match the
 *    server's hostname. The server must also have is a (possibly-empty) chain of intermediate
 *    certificates to establish trust from a root certificate to the server's certificate. The root

*[Fess Site Search](https://github.com/codelibs/fess-site-search)* ist eine kostenlose Alternative zur [Google Site Search](https://enterprise.google.com/search/products/gss.html). Weitere Details finden Sie in der [Dokumentation des FSS JS Generators](https://fss-generator.codelibs.org/docs/manual).

## Website

            c[ci++] = '|';
            NL.getChars(0, NL_LENGTH, c, ci);
            ci += NL_LENGTH;
        } while (si < length);

        ps.println(c);
    }

    /**
     * This is an alternative to the <code>java.lang.Integer.toHexString</code>
     * method. It is an efficient relative that also will pad the left side so
     * that the result is <code>size</code> digits.
     *

        }

        value = props.getProperty("jcifs.native.os");
        if (value != null) {
            this.nativeOs = value;
        }

        // Also support the alternative property name used in tests
        value = props.getProperty("jcifs.smb.client.nativeOs");
        if (value != null) {
            this.nativeOs = value;
        }

```

////

//// tab | Python 3.8+

```Python hl_lines="1  4"
{!> ../../docs_src/python_types/tutorial009.py!}
```

////

//// tab | Python 3.8+ alternative

```Python hl_lines="1  4"
{!> ../../docs_src/python_types/tutorial009b.py!}
```

////

#### Using `Union` or `Optional` { #using-union-or-optional }