def mac_addr=(val)
      state = val ? '' : 'no'
      mac = val ? val.tr(':', '').scan(/.{1,4}/).join('.') : ''
      set_args_keys(state: state, mac: mac)
      config_set('interface_hsrp_group', 'mac_addr', @set_args)
    end
def mac_addr=(val)
      state = val ? '' : 'no'
      mac = val ? val.tr(':', '').scan(/.{1,4}/).join('.') : ''
      set_args_keys(state: state, mac: mac)
      config_set('interface_hsrp_group', 'mac_addr', @set_args)
    end
CLI expects mac_addr to be in xxxx.xxxx.xxxx format
 so convert from xx:xx:xx:xx:xx:xx format