Hi JP,
I haven't tried migrating between databases before, but I took a quick look at the link you provided. The basic concept, of using SQLAlchemy's support for each database to read and write a table at a time with separate connections and sessions, seems reasonable as long as your table contents are on the smaller side.
Before anything else, I recommend going through the tutorial (
http://docs.sqlalchemy.org/en/rel_0_7/orm/tutorial.html) and verifying that your arguments to create_engine() allow you to query data from your sqlite database to be migrated and create tables and add rows to the mysql database you wish to migrate to.
After that, if you still have issues migrating, try to let us know
as much as possible about what happened. What parts of the process didn't work? Did you
get any error messages?
All the best,
Chris