There is no current way through the Python API to access the logs of removed jobs. However, the data-mining of historical job info (even for removed or archived jobs) is one of the areas we are looking to further develop in future versions of Qube.
At the present you will have to go out manually to the directory on the Supervisor where the job log files are stored. Alternatively, the location of those job logs can be configured in the qb.conf of the Supervisor to be stored on a network filesystem. One could then scan those job log directories directly with python or any other scripting language.