What happens underneath when I save to a model with ManyToMany relationships?

[LJ]

I have a Python script that will be called daily from a scheduled service or daemon.
The script uses MySQLdb to read a csv file and import data into a MySQL database that is used in my Django application.
Some of the models contain ManyToMany relationships.  I am directly inserting the relationships.
I thought that this was working great until I tried to query the models from my Django view.
For example, I have a list of students, and each student has one or more parents.  Even though the students_student_parents table that stores the student/parent relationship is updated by the script, when I run the query to get a list of parents, the list is empty.

        importedStudent = get_object_or_404(Student, pk=studentId)
        logger.info(importedStudent)
        the_parents = importedStudent.parents.all().values_list('id', flat=True)

It appears that I have one of two choices:
1) Figure out what really happens under the covers when I add a parent to a student in a Django form and call save() or save_m2m().
2) Instead of inserting data into my tables using MySQLdb cursor execute methods, would it be better for me to create a service in my Django application that my script can call?

Any suggestions?