Help opening "append" window from addon


I am trying to call the append window (Shift + F1) from an addon in order to add several automated steps after that action.
hovering the button tells me i should use:
but gives me an “Not a Library” error
So i guess this operator needs the args. But this is not what i need.

How should i proceed with this ?
Thanks for your help

bpy.ops.wm.append(‘INVOKE_DEFAULT’) ?