code: public function getList($sort = null)
  	{
  	    //Get the countries list
  	    $countries = $this->getCountries();
  
  	    //Sorting
  	    $validSorts = array(
  	        'name',
  	        'fullname',
  	        'iso_3166_2',
  	        'iso_3166_3',
  	        'capital',
  	        'citizenship',
  	        'currency',
  	        'currency_code',
  	        'calling_code'
          );
  
  	    if (!is_null($sort) && in_array($sort, $validSorts)){
  	        uasort($countries, function($a, $b) use ($sort) {
  	            if (!isset($a[$sort]) && !isset($b[$sort])){
  	                return 0;
  	            } elseif (!isset($a[$sort])){
  	                return -1;
  	            } elseif (!isset($b[$sort])){
  	                return 1;
  	            } else {
  	                return strcasecmp($a[$sort], $b[$sort]);
  	            }
  	        });
  	    }
  
  	    //Return the countries
  		return $countries;
  	}
docs: Returns a list of countries
  
  @param string sort
  
  @return array