if (node.previousSibling == null) {
        // requireNonNull is safe because we checked that not *both* siblings were null.
        keyList.head = requireNonNull(node.nextSibling);
      } else {
        node.previousSibling.nextSibling = node.nextSibling;
      }

      if (node.nextSibling == null) {
        // requireNonNull is safe because we checked that not *both* siblings were null.

  /**
   * No-op null-pointer test for {@link LongAdder} to override the {@link PackageSanityTests}
   * version, which checks package-private methods that we don't want to have to annotate as {@code
   * Nullable} because we don't want diffs from jsr166e.
   */
  public void testNulls() {}

  public void testOverflows() {
    LongAdder longAdder = new LongAdder();
    longAdder.add(Long.MAX_VALUE);

import com.google.caliper.Benchmark;
import org.jspecify.annotations.NullUnmarked;

/**
 * Simple benchmark: create, start, read. This does not currently report the most useful result
 * because it's ambiguous to what extent the stopwatch benchmark is being affected by GC.
 *
 * @author Kevin Bourrillion
 */
@NullUnmarked
public class StopwatchBenchmark {
  @Benchmark
  long stopwatch(int reps) {

      if (!compareAndSet(currentThread, DONE)) {
        waitForInterrupt(currentThread);
      }
      if (run) {
        if (error == null) {
          // The cast is safe because of the `run` and `error` checks.
          afterRanInterruptiblySuccess(uncheckedCastNullableTToT(result));
        } else {
          afterRanInterruptiblyFailure(error);
        }
      }
    }
  }

Make sure you create a [virtual environment](../virtual-environments.md){.internal-link target=_blank}, activate it, and then install it, for example:

```console
$ pip install python-multipart
```

This is because uploaded files are sent as "form data".

///

## Import `File` { #import-file }

Import `File` and `UploadFile` from `fastapi`:

{* ../../docs_src/request_files/tutorial001_an_py39.py hl[3] *}

 * multiple threads.
 *
 * <p>Because, in general, escaping operates on the code points of a string and not on its
 * individual {@code char} values, it is not safe to assume that {@code escape(s)} is equivalent to
 * {@code escape(s.substring(0, n)) + escape(s.substring(n))} for arbitrary {@code n}. This is
 * because of the possibility of splitting a surrogate pair. The only case in which it is safe to

      Cell<R, C, V> cell = cellList.get(i);
      R rowKey = cell.getRowKey();
      C columnKey = cell.getColumnKey();
      V value = cell.getValue();

      /*
       * These requireNonNull calls are safe because we construct the maps to hold all the provided
       * cells.
       */
      cellRowIndices[i] = requireNonNull(rowIndex.get(rowKey));
      Map<C, V> thisRow = requireNonNull(rows.get(rowKey));

        } catch (final NoSuchMethodException e) {
            fail("Constructor with Context parameter should exist");
        }
    }

    // Note: This test is simplified because complex Tomcat Context mocking
    // is difficult to maintain due to frequent API changes.
    // The focus is on testing the class structure and basic functionality
    // that can be verified without full integration testing.

import jnr.unixsocket.UnixSocket;
import jnr.unixsocket.UnixSocketAddress;
import jnr.unixsocket.UnixSocketChannel;

/**
 * Subtype UNIX socket for a higher-fidelity impersonation of TCP sockets. This is named "tunneling"
 * because it assumes the ultimate destination has a hostname and port.
 */
final class TunnelingUnixSocket extends UnixSocket {
  private final File path;
  private InetSocketAddress inetSocketAddress;

    ;;
    deconfigure|failed-upgrade)
    ;;

    # RedHat ####################################################
    0)
        STOP_REQUIRED=true
    ;;
    1)
        # Don't do anything on upgrade, because the preun script in redhat gets executed after the postinst (madness!)
    ;;

    *)
        echo "pre remove script called with unknown argument \`$1'" >&2
        exit 1
    ;;
esac

# Stops the service