Change text with str_replace

my_change_text_mmpu.php

<?php

/*
Replace or translate text strings that's not translatable with gettext.
*/

// Check page content and replace text strings
function my_change_text_mmpu( $text ) {

	global $pmpro_pages;

	if ( is_page( $pmpro_pages['levels'] ) ) {
				$text = str_replace( 'Membership Selections', 'Selections', $text );
	}
	return $text;
}
add_filter( 'the_content', 'my_change_text_mmpu', 25 );