old_contents: from django.db import models
  
  class Category(models.Model):
      name = models.CharField(max_length=50)
      number = models.CharField(max_length=50, unique=True)
      
      def __str__(self):
          return self.number
  
  
  class Subcategory(models.Model):
      name = models.CharField(max_length=50)
      category = models.ForeignKey(Category)
  
      def __str__(self):
          return self.name
  
  
  class Transaction(models.Model):
      IN = 'i'
      OUT = 'o'
      TYPE_CHOICES = (
              (IN, 'Money In'),
              (OUT, 'Money Out'),
      )
      transaction_type = models.CharField(max_length=5, choices=TYPE_CHOICES, default=OUT)
      category = models.ForeignKey(Category)
      date = models.DateTimeField()
      subcategory = models.ForeignKey(Subcategory, blank=True)
      comment = models.CharField(max_length=200, blank=True)
      amount = models.CharField(max_length=50)
      balance = models.CharField(max_length=50)
  
      def __str__(self):
          return self.transaction_type + amount
  
new_contents: from django.db import models
  
  class Category(models.Model):
      name = models.CharField(max_length=50)
      number = models.CharField(max_length=50, unique=True)
      
      def __str__(self):
          return self.number
  
  
  class Subcategory(models.Model):
      name = models.CharField(max_length=50)
      category = models.ForeignKey(Category)
  
      def __str__(self):
          return self.name
  
  
  class Transaction(models.Model):
      IN = 'i'
      OUT = 'o'
      TYPE_CHOICES = (
              (IN, 'Money In'),
              (OUT, 'Money Out'),
      )
      transaction_type = models.CharField(max_length=5, choices=TYPE_CHOICES, default=OUT)
      category = models.ForeignKey(Category)
      date = models.DateTimeField()
      subcategory = models.ForeignKey(Subcategory, blank=True)
      comment = models.CharField(max_length=200, blank=True)
      amount = models.CharField(max_length=50)
      balance = models.CharField(max_length=50)
      #Add the ForeignKey to accounts
  
      def __str__(self):
          return self.transaction_type + amount
  
subject: Add some TODO things