Wordpress: Custom excerpt size on any part of code

functions_custom.php

<?php

function custom_excerpt($new_length = 20, $new_more = '...') {
	add_filter('excerpt_length', function () use ($new_length) {
		return $new_length;
	}, 999);
 
	add_filter('excerpt_more', function () use ($new_more) {
		return $new_more;
	});
	
	$output = get_the_excerpt();
	$output = apply_filters('wptexturize', $output);
	$output = apply_filters('convert_chars', $output);
	$output = '<p>' . $output . '</p>';
	
	echo $output;
}