[Workaround] Jetbot do not appear in the Isasc Sim tutorial '8. Multiple Tasks'

Hi~

Problem
When I follow the tutorial ‘8. Multiple Tasks’ below of Isaac Sim, there happened that JetBot do not appear on screen:
8. Multiple Tasks

The error messages are here:

2022-05-27 07:55:40 [24,876,055ms] [Error] [asyncio] [/isaac-sim/kit/python/lib/python3.7/asyncio/base_events.py:1619] Task exception was never retrieved
future: <Task finished coro=<BaseSampleExtension._on_load_world.._on_load_world_async() done, defined at /isaac-sim/exts/omni.isaac.examples/omni/isaac/examples/base_sample/base_sample_extension.py:161> exception=TypeError(“find_unique_string_name() got an unexpected keyword argument ‘initial_name’”)>
Traceback (most recent call last):
File “/isaac-sim/exts/omni.isaac.examples/omni/isaac/examples/base_sample/base_sample_extension.py”, line 162, in _on_load_world_async
await self._sample.load_world_async()
File “/isaac-sim/exts/omni.isaac.examples/omni/isaac/examples/base_sample/base_sample.py”, line 48, in load_world_async
await self._world.reset_async()
File “/isaac-sim/exts/omni.isaac.core/omni/isaac/core/world/world.py”, line 196, in reset_async
task.set_up_scene(self.scene)
File “/isaac-sim/exts/omni.isaac.examples/omni/isaac/examples/user_examples/hello_world.py”, line 33, in set_up_scene
initial_name=“fancy_jetbot”, is_unique_fn=lambda x: not self.scene.object_exists(x)
TypeError: find_unique_string_name() got an unexpected keyword argument ‘initial_name’

Environment
Isaac Sim was run on Ubuntu desktop environment in AWS EC2 Isaac Sim Container

Workaround
Though I don’t know the reason, for the first part of the tutorial code, by substituting the code for Jetbot as below, it worked.
Before:

#Find a unique scene name
jetbot_name = find_unique_string_name(
initial_name=“fancy_jetbot”, is_unique_fn=lambda x: not self.scene.object_exists(x)
)
# Find a unique prim path
jetbot_prim_path = find_unique_string_name(
initial_name="/World/Fancy_Jetbot", is_unique_fn=lambda x: not is_prim_path_valid(x)
)
self._jetbot = scene.add(Jetbot(prim_path=jetbot_prim_path,
name=jetbot_name,
position=np.array([0, 30, 0])))

After(= the code in the previous tutorial step):

self._jetbot = scene.add(Jetbot(prim_path=jetbot_prim_path,
name=jetbot_name,
position=np.array([0, 30, 0])))

Remaining
I don’t know the workaround for the second part code of the tutorial