Model in the abstract class table inheritance

# Main table 
class Base (models.Model): 
    create_time = models.DateTimeField (auto_now_add = True) # Create a time 
    update_time = models.DateTimeField (auto_now = True) # Updated 
    class Meta: 
        abstract = True # must write

class Stu(Base,models.Model):
    name = models.CharField(max_length=32)
    img = models.CharField(max_length=255)
    duo = models.ManyToManyField(to='Kc',related_name='sss')#
    class Meta:
        db_table='stu'