old_contents: from django.db import models
  from django.contrib.auth.models import User
  from django.db.models.signals import post_save
  SEX_CHOICES = (
          ('Male', 'Male'),
      	('Female', 'Female'),
      )
  class UserProfile(models.Model):
  	user = models.OneToOneField(User)
  	sex = models.CharField(max_length = 6, choices = SEX_CHOICES)
  	birthday = models.DateField(null = True)
  
  def create_user_profile(sender, instance, created, **kwargs):
      if created:
          UserProfile.objects.create(user = instance)
  
  post_save.connect(create_user_profile, sender = User)
new_contents: from django.db import models
  from django.contrib.auth.models import User
  from django.db.models.signals import post_save
  SEX_CHOICES = (
          ('Male', 'Male'),
      	('Female', 'Female'),
      )
  class UserProfile(models.Model):
  	user = models.OneToOneField(User)
  	sex = models.CharField(max_length = 6, choices = SEX_CHOICES)
  	birthday = models.DateField(null = True)
  	def __unicode__(self):
  		return self.user.get_full_name()
  
  def create_user_profile(sender, instance, created, **kwargs):
      if created:
          UserProfile.objects.create(user = instance)
  
  post_save.connect(create_user_profile, sender = User)
subject: Set User Profile Unicode Function