docs: @Beta
    public static <K, V> ImmutableBiMap<K, V> copyOf(
        Iterable<? extends Entry<? extends K, ? extends V>> entries) {
      Entry<?, ?>[] entryArray = Iterables.toArray(entries, EMPTY_ENTRY_ARRAY);
      switch (entryArray.length) {
        case 0:
          return of();
        case 1:
          @SuppressWarnings("unchecked") // safe covariant cast in this context
          Entry<K, V> entry = (Entry<K, V>) entryArray[0];
          return of(entry.getKey(), entry.getValue());
        default:
          return new RegularImmutableBiMap<K, V>(entryArray);
      }
    }