you can also try the ProgIDFromCLSID from pythoncom

https://timgolden.me.uk/pywin32-docs/pythoncom__ProgIDFromCLSID_meth.html

this raise an exception if the object is not found

>>> pythoncom.ProgIDFromCLSID("Inventor.NoApplication")
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
pywintypes.com_error: (-2147221005, 'Invalid class string', None, None)
>>> pythoncom.ProgIDFromCLSID("Inventor.Application")
u'Inventor.Application.1'