class MySingleton {
 public static function numberByWhat( $number ) {
   return $number + 100;
 }
 public static function someCharacters( $string ) {
   return $string + 'abc';
 }
}

class MyOtherSingleton {
  public static function getImage( $url ) {
    return '<img src="' . $url . MySingleton::numberByWhat( $50 ) . '">';
  }
  public static function getTextById( $id ) {
    if( $id == 3 ) {
      return 'this is my text' . MySingleton::someCharacters( 'Yeah' );
    }
  }
}

function run() {
  echo MyOtherSingleton::getImage( 'http://www.example.com/image.png' );
  echo MyOtherSingleton::getTextById( 3 );
}

run();