ModuleNotFoundError: No module named 'omni.importer'

Hi, I was trying to add my own .urdf asset on top of the example provided by

To import my own .urdf, I used the following lines:

import omni.kit.commands
from omni.importer.urdf import _urdf

according to the tutorial: 5.1. Import URDF — Omniverse IsaacSim latest documentation

However, I got ModuleNotFoundError: No module named ‘omni.importer’

My Isaac Sim version is 2023.1.1 and I have tried reinstalling it but didn’t work. Besides, I have also tried

PYTHON_PATH -m pip install omni.importer.urdf

which returned

ERROR: Could not find a version that satisfies the requirement omni.importer.urdf (from versions: none)
ERROR: No matching distribution found for omni.importer.urdf

Additionally, I tried importing urdf file using following lines

file_name = “ScaleBike_NoPend_V3.urdf”
result, prim_path = omni.kit.commands.execute( “URDFParseAndImportFile”, urdf_path=“{}/{}”.format(root_path, file_name),dest_path=dest_path)

with reference to 5.1. Import URDF — Omniverse IsaacSim latest documentation, which yields

[Error] [omni.kit.commands.command] Can’t execute command: “URDFParseAndImportFile”, it wasn’t registered or ambigious.

How could these be solved? Any advice would be appreciated.