wordpress.org – Add link to wordpress field data

This code displays “@ fielddata” how I can add link to the artist?
Link is “https://rule34cartoon.com/?s=fielddata” .

<center>
<?php
$artist = get_post_meta(get_the_ID(), 'artist', true);
if ( $artist ) :
    echo '© ' . $artist;
endif;
?>
</center>