I'm doing something that doesn't feel very efficient. From my code below, you can probably see that I'm trying to allow for multiple profiles of different types attached to my custom user object (Person). One of those profiles will be considered a default and should have an accessor from the Person class. Can this be done better?

from django.db import models
from django.contrib.auth.models import User, UserManager


class Person(User):

    public_name = models.CharField(max_length=24, default="Mr. T")

    objects = UserManager()

    def save(self):
        self.set_password(self.password)
        super(Person, self).save()


    def _getDefaultProfile(self):

        def_teacher = self.teacher_set.filter(default=True)
        if def_teacher: return def_teacher[0]

        def_student = self.student_set.filter(default=True)
        if def_student: return def_student[0]

        def_parent  = self.parent_set.filter(default=True)
        if def_parent:  return def_parent[0]

        return False
    profile = property(_getDefaultProfile)


    def _getProfiles(self):
        # Inefficient use of QuerySet here. Tolerated because the QuerySets should be very small.
        profiles = []
        if self.teacher_set.count(): profiles.append(list(self.teacher_set.all()))
        if self.student_set.count(): profiles.append(list(self.student_set.all()))
        if self.parent_set.count():  profiles.append(list(self.parent_set.all()))

        return profiles
    profiles = property(_getProfiles)




class BaseProfile(models.Model):

    person = models.ForeignKey(Person)
    is_default = models.BooleanField(default=False)

    class Meta:
        abstract = True


class Teacher(BaseProfile):
    user_type = models.CharField(max_length=7, default="teacher")


class Student(BaseProfile):
    user_type = models.CharField(max_length=7, default="student")


class Parent(BaseProfile):
    user_type = models.CharField(max_length=7, default="parent")