'set update command'

def set_update_cmd(self):

    if (not self.changed):
        return
    if (self.state == 'present'):
        self.updates_cmd.append(('ip    vpn-instance    %s' % self.vrf))
        if self.description:
            self.updates_cmd.append(('description    %s' % self.description))
    else:
        self.updates_cmd.append(('undo    ip    vpn-instance    %s' % self.vrf))
