Models.py

$ cat user/models.py
from django.db import models
import city

class User(models.Model):
    username = models.CharField(max_length=32)
    password = models.CharField('encrypted and salted', max_length=64)
    salt = models.CharField('password salt', max_length=32, editable=False)
    first_name = models.CharField(max_length=24)
    last_name = models.CharField(max_length=48, blank=True)
    city = models.ForeignKey(City, null=True)