'Updates qty or amount at row level
:param update_modified: If true, updates `modified` and `modified_by` for target parent doc'

def update_qty(self, update_modified=True):

    for args in self.status_updater:
        if (self.docstatus == 1):
            args[u'cond'] = (u'    or    parent="%s"' % self.name.replace(u'"', u'"'))
        else:
            args[u'cond'] = (u'    and    parent!="%s"' % self.name.replace(u'"', u'"'))
        self._update_children(args, update_modified)
        if (u'percent_join_field' in args):
            self._update_percent_field_in_targets(args, update_modified)
