Adds new targets to the span with the specified ids
        @type list_ids: list
        @param list_ids: list of identifiers

def create_from_ids(self,list_ids):
        """
        Adds new targets to the span with the specified ids
        @type list_ids: list
        @param list_ids: list of identifiers
        """
        for this_id in list_ids:
            new_target = Ctarget()
            new_target.set_id(this_id)
            self.node.append(new_target.get_node())