How do I access an Oracle db without installing Oracle's client and cx_Oracle?

An excerpt from https://forum.omz-software.com/topic/184/oracle-database:

There's no pure python client for Oracle and likely never will be. Even wonderful third-party toolsets like SQLalchemy still rely on cx_Oracle underneath to do the actual communication to the Oracle database servers.

—also, deciding by Google, the answer is no: there do not seem to be any pure Python Oracle clients in existence as of today.

Usually, all you need are the libraries, which don't necessarily require sudo rights. Extract them to a place the software will be able to read from and set the following environment variables accordingly:

ORACLE_HOME=path/to/where/you/extracted/libs
TNS_ADMIN=path/to/tnsnames.ora

I have had best luck skipping tnsnames, and just specifying the host, port, etc in the connection, but it's quite possible you'll need it for cx_oracle...I don't remember from when I used it ages ago.