Can someone tell me what these functions mean

I was trying to take a link out of my footer that leads to a spam webhosting site and i keep getting the “This theme is released under creative commons licence, all links in the footer should remain intacted” So upon further investigation i found 4 functions encoded in rot13. I decoded them but I dont know how they work. how do i go about changing the footer? i dont want to change anything just remove that one url.

here are the functions decoded:

these two are in my header.php file

function check_f_footer(){if(!(function_exists(“check_footer”)&&function_exists(“check_header”))){echo(\’This theme is released under creative commons licence, all links in the footer should remain intact\’);die;}}check_f_footer();

function check_functions(){if(!file_exists(dirname(__FILE__).”/functions.php”)){echo(\’This theme is released under creative commons licence, all links in the footer should remain intact\’);die;}}check_functions();

these 2 are in my functions.php file

function check_header(){if(!(function_exists(“check_functions”)&&function_exists(“check_f_footer”))){echo(\’This theme is released under creative commons licence, all links in the footer should remain intact\’);die;}}

function check_footer(){$l=\’Theme by Dedicated Web Hosting\’;$f=dirname(__FILE__).\’/footer.php\’;$fd=fopen($f,\’r\’);$c=fread($fd,filesize($f));fclose($fd);if(strpos($c,$l)==0){echo \’This theme is released under creative commons licence, all links in the footer should remain intact\’;die;}}check_footer();