How to change the Launchpad Id? 如何更改Launchpad Id？

目前这个Launchpad Id是我使用Ubuntu One帐号登录时，系统自动生成的，我不想要这个id，但是在设置里，我无法更改Launchpad Id，请问如何更改Launchpad Id？我想将id更改为HuanLee1993
Currently this Launchpad Id is when I use Ubuntu One account login, the system automatically generates, I do not want this id, but in the settings, I can not change Launchpad Id, how to change the Launchpad Id? I want to change the id to HuanLee1993.