code: public function getCalendars()
  	{
  		if (!$this->User->isAdmin && !\is_array($this->User->calendars))
  		{
  			return array();
  		}
  
  		$arrCalendars = array();
  		$objCalendars = $this->Database->execute("SELECT id, title FROM tl_calendar ORDER BY title");
  
  		while ($objCalendars->next())
  		{
  			if ($this->User->hasAccess($objCalendars->id, 'calendars'))
  			{
  				$arrCalendars[$objCalendars->id] = $objCalendars->title;
  			}
  		}
  
  		return $arrCalendars;
  	}
docs: Get all calendars and return them as array
  
  @return array