title: Include external files in functions.php WordPress
body: <p>In my WordPress I have a functions.php file containing 1500 lines of code. </p>
  
  <p>Most of this code comes from a program I wrote that connects to an API and sends data from WordPress to it. I am not a WordPress developer, so I do not know if this is possible. Can you make a different file to keep functions.php clean and then include the external file inside the functions.php? </p>