`Optional[EenType]` is eigenlijk een snelkoppeling voor `Union[EenType, None]`, ze zijn equivalent.

Dit betekent ook dat je in Python 3.10 `EenType | None` kunt gebruiken:

//// tab | Python 3.10+

```Python hl_lines="1"
{!> ../../docs_src/python_types/tutorial009_py310.py!}
```

////

  @CanIgnoreReturnValue
  CacheBuilder<K, V> keyEquivalence(Equivalence<Object> equivalence) {
    checkState(keyEquivalence == null, "key equivalence was already set to %s", keyEquivalence);
    keyEquivalence = checkNotNull(equivalence);
    return this;
  }

  Equivalence<Object> getKeyEquivalence() {
    return MoreObjects.firstNonNull(keyEquivalence, getKeyStrength().defaultEquivalence());
  }

  /**

   * multiple multisets in series.
   *
   * @since 12.0
   */
  public static class Builder<E> extends ImmutableMultiset.Builder<E> {
    /**
     * Creates a new builder. The returned builder is equivalent to the builder generated by {@link
     * ImmutableSortedMultiset#orderedBy(Comparator)}.
     */
    public Builder(Comparator<? super E> comparator) {
      super(TreeMultiset.<E>create(checkNotNull(comparator)));

  // element of the list has the short hash value h.
  //
  // A wrinkle here is that the value 0 (called UNSET in the code) is used as the equivalent of a
  // null pointer. If `table[h] == 0` that means there are no keys in the map whose short hash is h.
  // If the `next` bits in `entries[i]` are 0 that means there are no further entries for the given

            fromIterator.remove();
          }
        };
  }

  /**
   * Returns the reversed view of this converter, which converts {@code this.convert(a)} back to a
   * value roughly equivalent to {@code a}.
   *
   * <p>The returned converter is serializable if {@code this} converter is.
   *
   * <p><b>Note:</b> you should not override this method. It is non-final for legacy reasons.
   */

function must not contain the package name component (for example,
function <code>Syscall</code> in package <code>syscall</code> should
use the name <code>·Syscall</code> instead of the equivalent name
<code>syscall·Syscall</code> in its <code>TEXT</code> directive).
For more complex situations, explicit annotation is needed.
These annotations use pseudo-instructions defined in the standard

    private void readObject(ObjectInputStream stream) throws InvalidObjectException {
    throw new InvalidObjectException("Use SerializedForm");
  }

  /**
   * Returns a new builder. The generated builder is equivalent to the builder created by the {@link
   * Builder} constructor.
   */
  public static <E> Builder<E> builder() {
    return new Builder<>();
  }

  /**

  // element of the list has the short hash value h.
  //
  // A wrinkle here is that the value 0 (called UNSET in the code) is used as the equivalent of a
  // null pointer. If `table[h] == 0` that means there are no keys in the map whose short hash is h.
  // If the `next` bits in `entries[i]` are 0 that means there are no further entries for the given

    except NameError:
      answer = input(question)  # pylint: disable=bad-builtin
  except EOFError:
    answer = ''
  return answer


def symlink_force(target, link_name):
  """Force symlink, equivalent of 'ln -sf'.

  Args:
    target: items to link to.
    link_name: name of the link.
  """
  try:
    os.symlink(target, link_name)
  except OSError as e:
    if e.errno == errno.EEXIST:

        }
    }

    /**
     * Converts a robots.txt pattern to a regular expression.
     *
     * @param path The robots.txt pattern to convert
     * @return The equivalent regular expression
     */
    protected String convertRobotsTxtPatternToRegex(final String path) {
        String newPath = path.replace(".", "\\.").replace("?", "\\?").replace("*", ".*");