src/model/admin/class-rating.php
public function set_movie_rating( $post_id, $rating ) {

		if ( ! add_post_meta( $post_id, 'imdbRating', $rating, true ) ) {
			update_post_meta( $post_id, 'imdbRating', $rating );
		}
	}
public function set_movie_rating( $post_id, $rating ) {

		if ( ! add_post_meta( $post_id, 'imdbRating', $rating, true ) ) {
			update_post_meta( $post_id, 'imdbRating', $rating );
		}
	}
Set movie rating.

@param string    $post_id  → post id.
@param int|float $rating  → movie rating.