function my_custom_ticket_header($collumns){
	$collumns = array( 'type' => __('Ticket Type','dbem'), 'price' => __('Price','dbem'), 'spaces' => __('Spaces','dbem'), 'available_spaces' => __('Available Spaces','dbem') );
	return $collumns;
}
add_filter('em_booking_form_tickets_cols','my_custom_ticket_header',1,1);<?xml version="1.0" encoding="UTF-8"?>
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