Modify default event total spaces

<?php
/*
for more information on adding this snippet to your site, see here
http://wp-events-plugin.com/tutorials/how-to-safely-add-php-code-to-wordpress/
*/

/**
 * Changes the default total spaces available for booking when creating a new event.
 * @param EM_Event $EM_Event
 */
function my_em_default_total_spaces($EM_Event) {
    if( empty($EM_Event->event_id) ){
        $EM_Event->event_spaces = 30; //set the default Total Spaces you'd like here
    }
}
add_action('em_event', 'my_em_default_total_spaces', 10, 1);