Don’t show byline if by author X

<?php define ('AUTHOR_X_ID', '16');
$author_id = get_the_author_ID();

if ( $author_id != AUTHOR_X_ID ) {
  display byline
}; ?>

Wow, much easier than I expected! Thanks so much!

How does this work when there is NO FUNCTION called get_the_author_ID()?

If used in a The Loop then something like:

<?php
$author_id = $post->post_author;
if ( $author_id != 1 ) {
  //display byline for all but user ID 1
}
?>

Related:
How do I determine a Post, Page, Category, Tag, Link, Link Category, or User ID?
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