Exports this object into a LEMS XML object

def toxml(self):
        """
        Exports this object into a LEMS XML object
        """
        chxmlstr = ''

        for with_ in self.withs:
            chxmlstr += with_.toxml()

        for event_connection in self.event_connections:
            chxmlstr += event_connection.toxml()

        for child_instance in self.child_instances:
            chxmlstr += child_instance.toxml()

        for multi_instantiate in self.multi_instantiates:
            chxmlstr += multi_instantiate.toxml()

        for for_each in self.for_eachs:
            chxmlstr += for_each.toxml()

        if chxmlstr:
            xmlstr = '<Structure>' + chxmlstr + '</Structure>'
        else:
            xmlstr = ''

        return xmlstr