I was trying to connect oracle database using python like below.
import cx_Oracle
conn = cx_Oracle.connect(\'user/password@host:port/database\')
This seems a problem with version 6.X.This problem didnot appeared in 5.X.But for my case a little workaround worked.I installed in my physical machine and only thing that i need to do was a pc reboot or reopen the terminal as i have added in the path of environment variables.You can try to install in physical machine instead using azure notebooks.