Account: card_number and pin might be empty, credit defaults to 0

cash/models.py

@@ -4,10 +4,10 @@ from django.contrib.auth.models import User
 
 class Account(models.Model):
 	user = models.OneToOneField(User)
-	card_number = models.CharField(max_length=32, unique=True)
-	pin = models.CharField(max_length=32)
+	card_number = models.CharField(max_length=32, unique=True, blank=True)
+	pin = models.CharField(max_length=32, blank=True)
 	daily_digest = models.BooleanField()
-	credit = models.IntegerField()
+	credit = models.IntegerField(default=0)
 
 	def __unicode__(self):
 		return self.user.username