Hello Günter,
I have checked this and find out that the symbol ZN20RTEIPC_ObjectManager8InstanceEv is missing in 7.9.08.03 dbmmodule.so.
With 7.9.08.08 and 7.8.02.35 it works, You should install a newer version
The python package is not installed as default for a client with SAPINST. But you can install it separate by download the server or client and calling
SDBINST -package "Redist Python"
Kind regards,
Burkhard