public final class Callables {
  private Callables() {}

  /** Creates a {@code Callable} which immediately returns a preset value each time it is called. */
  public static <T extends @Nullable Object> Callable<T> returning(@ParametricNullness T value) {
    return () -> value;
  }

  /**
   * Creates an {@link AsyncCallable} from a {@link Callable}.
   *

        }
      }
    }
  }

  /**
   * If the graph is undirected, each unordered [node, otherNode] pair (except self-loops) will be
   * visited twice if there is an edge connecting them. To avoid returning duplicate {@link
   * EndpointPair}s, we keep track of the nodes that we have visited. When processing endpoint
   * pairs, we skip if the "other node" is in the visited set, as shown below:
   *
   * <pre>

    } catch (UnsupportedOperationException e) {
      return;
    }

    Set<Entry<K, V>> entrySet = map.entrySet();
    if (supportsRemove) {
      try {
        entrySet.retainAll(null);
        // Returning successfully is not ideal, but tolerated.
      } catch (NullPointerException tolerated) {
      }
    } else {
      try {
        entrySet.retainAll(null);

public final class Callables {
  private Callables() {}

  /** Creates a {@code Callable} which immediately returns a preset value each time it is called. */
  public static <T extends @Nullable Object> Callable<T> returning(@ParametricNullness T value) {
    return () -> value;
  }

  /**
   * Creates an {@link AsyncCallable} from a {@link Callable}.
   *

/// tip

Now we use `response_model=HeroPublic` instead of the **return type annotation** `-> HeroPublic` because the value that we are returning is actually *not* a `HeroPublic`.

If we had declared `-> HeroPublic`, your editor and linter would complain (rightfully so) that you are returning a `Hero` instead of a `HeroPublic`.

import (
	"bufio"
	"bytes"
	"encoding/binary"
	"flag"
	"fmt"
	"hash/crc32"
	"log"
	"os"
	"strings"

	"github.com/dchest/siphash"
	"github.com/google/uuid"
)

// hashes the key returning an integer based on the input algorithm.
// This function currently supports
// - SIPMOD
func sipHashMod(key string, cardinality int, id [16]byte) int {
	if cardinality <= 0 {
		return -1
	}

// with the Op field set to "open", the Path field set to name,
// and the Err field describing the problem.
//
// Open should reject attempts to open names that do not satisfy
// ValidPath(name), returning a *PathError with Err set to
// ErrInvalid or ErrNotExist.
func (ffs *fakeFsWithFakeFds) Open(name string) (fs.File, error) {
	f, err := ffs.ReadDirFS.Open(name)
	if err != nil {
		return nil, err
	}

 * which has a method {@code getChildren()} that retrieves its successors in a graph:
 *
 * <pre>{@code
 * someGraphAlgorithm(startNode, MyNode::getChildren);
 * }</pre>
 *
 * <p>If you have some other mechanism for returning the successors of a node, or one that doesn't
 * return an {@code Iterable<? extends N>}, then you can use a lambda to perform a more general
 * transformation:
 *
 * <pre>{@code

   * next} field is lazily initialized. The type of that field would be {@code @Nullable T}, and the
   * code would be responsible for populating a "real" {@code T} (which might still be the value
   * {@code null}!) before returning it to callers. Depending on how the code is structured, a
   * nullness analysis might not understand that the field has been populated. To avoid that problem

 * which has a method {@code getParents()} that retrieves its predecessors in a graph:
 *
 * <pre>{@code
 * someGraphAlgorithm(startNode, MyNode::getParents);
 * }</pre>
 *
 * <p>If you have some other mechanism for returning the predecessors of a node, or one that doesn't
 * return a {@code Iterable<? extends N>}, then you can use a lambda to perform a more general
 * transformation:
 *
 * <pre>{@code