code: public function interStore($destination, $set, ...$sets): int
      {
          array_unshift($sets, $set);
          array_unshift($sets, $this);
          $keys = [];
          foreach ($sets as $key) {
              $keys[] = ($key instanceof self) ? $key->key : $key;
          }
          if ($destination instanceof self) {
              $destination = $destination->key;
          }
  
          return $this->redis->sinterstore($destination, $keys);
      }
docs: @param string|self $destination Key or RedisSet that will hold the resulting set.
  @param string|self $set         First set or key.
  @param array<int, string|self> $sets,...     More sets or keys. Can be mixed.
  
  @return int The number of elements in the resulting set.