PHP8.0でWordPressの「Attempt to read property "ID" on null」のエラーを解決したい ### PHP7.3PHP8.0WordPress ### ( ! ) Warning: Attempt to read property "ID" on null in //.php on line ### <?php $post_id = $post->ID; ### PHP 8.0 WordPress 5.8.2

1. $post_id = 1
2.