>>> bpy.context.screen.areas[3].spaces.active.params.filename 'geometry_nodes\\procedural_hair_node_assets.blend\\NodeTree\\Braid Hair Curves' 
If the asset browser area on the window has been identified, it is useful to learn the information from the console.
In the example, it is "bpy.context.screen.areas[3]", but the number will vary depending on the environment.
The area can be identified
by https://github.com/Pullusb/devTools
which is an add-on that provides a convenient button on the console. 