error: (1146, "Table 'mydb.django_session' doesn't exist")

Because there is no Django in the database table_session.

Execute the command at the terminal to migrate the data structure

$ python manage.py migrate

After executing the above command, the output results are all OK. You can see that many tables have been added to the database table, The details are as follows

# By default 10 tables are automatically created in our database, as follows.
MariaDB [mydemo]> show tables;
+----------------------------+
| Tables_in_mydemo           |
+----------------------------+
| auth_group                 |
| auth_group_permissions     |
| auth_permission            |
| auth_user                  |
| auth_user_groups           |
| auth_user_user_permissions |
| django_admin_log           |
| django_content_type        |
| django_migrations          |
| django_session             |
| stu                        |
+----------------------------+
11 rows in set (0.00 sec)

Then it was solved