windows error not affecting simulation either/or visualisation

[jim-sharples]

$ python3 simpler_sim.py
Exception in thread Thread-2:
Traceback (most recent call last):
File "C:\Users\Sharples\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.12_qbz5n2kfra8p0\LocalCache\local-packages\Python312\site-packages\matplotlib\backend_bases.py", line 2961, in _wait_cursor_for_draw_cm
self.canvas.set_cursor(tools.Cursors.WAIT)
File "C:\Users\Sharples\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.12_qbz5n2kfra8p0\LocalCache\local-packages\Python312\site-packages\matplotlib\backends_backend_tk.py", line 434, in set_cursor
self.tkcanvas.configure(cursor=cursord[cursor])
File "C:\Program Files\WindowsApps\PythonSoftwareFoundation.Python.3.12_3.12.1008.0_x64__qbz5n2kfra8p0\Lib\tkinter_init.py", line 1721, in configure
return self.configure('configure', cnf, kw)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "C:\Program Files\WindowsApps\PythonSoftwareFoundation.Python.3.12_3.12.1008.0_x64__qbz5n2kfra8p0\Lib\tkinter_init.py", line 1711, in _configure
self.tk.call(_flatten((self._w, cmd)) + self._options(cnf))
RuntimeError: main thread is not in main loop

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "C:\Program Files\WindowsApps\PythonSoftwareFoundation.Python.3.12_3.12.1008.0_x64__qbz5n2kfra8p0\Lib\threading.py", line 1073, in _bootstrap_inner
self.run()
File "C:\Program Files\WindowsApps\PythonSoftwareFoundation.Python.3.12_3.12.1008.0_x64__qbz5n2kfra8p0\Lib\threading.py", line 1431, in run
self.function(*self.args, **self.kwargs)
File "C:\Users\Sharples\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.12_qbz5n2kfra8p0\LocalCache\local-packages\Python312\site-packages\scenebuilder\scenebuilder.py", line 179, in _hide_warning
self._update()
File "C:\Users\Sharples\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.12_qbz5n2kfra8p0\LocalCache\local-packages\Python312\site-packages\scenebuilder\scenebuilder.py", line 508, in _update
self.fig.canvas.draw()
File "C:\Users\Sharples\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.12_qbz5n2kfra8p0\LocalCache\local-packages\Python312\site-packages\matplotlib\backends\backend_tkagg.py", line 10, in draw
super().draw()
File "C:\Users\Sharples\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.12_qbz5n2kfra8p0\LocalCache\local-packages\Python312\site-packages\matplotlib\backends\backend_agg.py", line 385, in draw
with (self.toolbar._wait_cursor_for_draw_cm() if self.toolbar
File "C:\Program Files\WindowsApps\PythonSoftwareFoundation.Python.3.12_3.12.1008.0_x64__qbz5n2kfra8p0\Lib\contextlib.py", line 137, in enter
return next(self.gen)
^^^^^^^^^^^^^^
File "C:\Users\Sharples\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.12_qbz5n2kfra8p0\LocalCache\local-packages\Python312\site-packages\matplotlib\backend_bases.py", line 2964, in _wait_cursor_for_draw_cm
self.canvas.set_cursor(self._last_cursor)
File "C:\Users\Sharples\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.12_qbz5n2kfra8p0\LocalCache\local-packages\Python312\site-packages\matplotlib\backends_backend_tk.py", line 434, in set_cursor
self.tkcanvas.configure(cursor=cursord[cursor])
File "C:\Program Files\WindowsApps\PythonSoftwareFoundation.Python.3.12_3.12.1008.0_x64__qbz5n2kfra8p0\Lib\tkinter_init.py", line 1721, in configure
return self.configure('configure', cnf, kw)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "C:\Program Files\WindowsApps\PythonSoftwareFoundation.Python.3.12_3.12.1008.0_x64__qbz5n2kfra8p0\Lib\tkinter_init.py", line 1711, in _configure
self.tk.call(_flatten((self._w, cmd)) + self._options(cnf))
RuntimeError: main thread is not in main loop
Simulation took 4.169423499999539 seconds