The context of this is explanined over at https://www.codingninja.co.uk/the-joys-of-migrating-from-sql-server-to-mariadb/
First clone down the repo:
$ git clone https://github.com/coding-ninja/mssql-guid-transform
$ cd mssql-guid-transform/
Next just modify the script to add in your MySql connection details as can be found from line 30:
#====================================================
# configuration
#====================================================
DB_HOST = "your_host"
DB_USER = "your_user"
DB_PASS = "your_password"
DB_NAME = "your_db_name"
Now simply run the python script (this is Python 2.7 IIRC):
$ python transform.py