read slave , read-write master setup

Question

I have a Flask,SQLAlchemy webapp which uses a single mysql server. I want to expand the database setup to have a read-only slave server such that I can spread the reads between both master and slave while continuing to write to the master db server.

I have looked at few of options and I believe I can't do this with plain SQLAlchemy. Instead Im planning to create 2 database handles in my webapp, one each for master and slave db servers. Then using a simple random value use either the master/slave db handle for "SELECT" operations.

However Im not sure if this is the right way to go with using SQLAlchemy. Any suggestion/tips on how to pull this off ? Thanks in advance.