How to copy CAD model to meshing model in Fault-Tolerant Meshing workflow?

[HXC1230]

I want to use FTM workflow, in the example"exhaust_system_settings_api.py", the cad models are copied to "meshing model" by the followed codes:
meshing_session.PartManagement.Node["Meshing Model"].Copy(
Paths=[
"/dirty_manifold-for-wrapper," + "1/dirty_manifold-for-wrapper,1/main,1",
"/dirty_manifold-for-wrapper," + "1/dirty_manifold-for-wrapper,1/flow-pipe,1",
"/dirty_manifold-for-wrapper," + "1/dirty_manifold-for-wrapper,1/outpipe3,1",
"/dirty_manifold-for-wrapper," + "1/dirty_manifold-for-wrapper,1/object2,1",
"/dirty_manifold-for-wrapper," + "1/dirty_manifold-for-wrapper,1/object1,1",
]
)

I don't understan the meaning of ID "1". Do I have to list all the model trees in order to copy them into the meshing model?
I attempted to import a simple model and modified this code, but an error occurred：

meshing_session.PartManagement.Node["Meshing Model"].Copy(
Paths=[
"/pipe," + "1/pipe,1/housing,1",
"/pipe," + "1/pipe,1/outlet,1",
"/pipe," + "1/pipe,1/inlet,1",
"/pipe," + "1/pipe,1/cons1,1",
"/pipe," + "1/pipe,1/const2,1",
"/pipe," + "1/pipe,1/fan,1",
]
)

Error: There are no objects in the Meshing Model tree. Drag and drop nodes from the CAD Model tree onto the Meshing Model tree, or right-click node(s) in the CAD Model tree and use the context menu.
Error Object: #f

What should I do to use FTM workflow to create mesh for the local model?