code: public function chatCreateGroup($groupName, array $peers)
      {
          $groupName = $this->escapeStringArgument($groupName);
          $peerList  = $this->formatPeers($peers);
  
          return $this->exec('create_group_chat ' . $groupName . ' ' . $peerList);
      }
docs: Create a group chat with $peers
  
  @param string $groupName The name of the group chat
  @param array  $peers     All peers to be included in chat
  @return bool|string