When i place custom code

Hi, I can see from your plugin that if an image has not been uploaded to a post… the post can have an image, specific to the category it is in…

I have tried adding the to my functions.php but it gives me an error, even before I upload it… Am I placing it in the wrong place?

Kind regards

Gary

function dfi_category ( $dfi_id, $post_id ) {
  // all which have 'animals' as a category
  if ( has_category( 'animals', $post_id ) ) {

    //sub category
    if ( has_category( 'cats', $post_id ) ) {
      return 7; // cats img
    } else if has_category( 'dogs', $post_id ) {
      return 8; // dogs img
    }

    return 6; // default animals picture
  }
  return $dfi_id; // the original featured image id
}
add_filter( 'dfi_thumbnail_id', 'dfi_category', 10, 2 );

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