Symptom

Python code completion does not work in PyCrust and in PTV Visum menu 'Scripts->VisumAddIn->Python Console'.
Only commands beginning with '_' are shown.
Error message contains "gencache.py", like 'C:\Program Files\Python39\lib\site-packages\win32com\client\gencache.py, line ..., in ...'

Resolution

Python code completion will work again when the subfolder 'gen-py' in the %TMP% folder is deleted.
This is the Python cache (default location 'C:\Users\\AppData\Local\Temp\gen_py').
In addition, please ensure that Visum is registered as COM server.