[PyQt] How can I promote some custom widgets in qt-designer?

[Kermit Mei]

Hello, community!

In Qt designer, I can promote some custom widgets. If I wrote qt/c++
code, then I must set the items "Promoted class name:" and "Header file"
in Qt designer's "Promoted Widgets" window.

Now, as for pyqt4, how can I promote some widgets in qt-designer?
How to pointed the "Header file" item?

Thanks

Kermit Mei