old_contents: from django.db import models
  
  
  class Chef(models.Model):
      first_name = models.CharField(max_length=60)
      last_name = models.CharField(max_length=60)
  
  
  class Pizza(models.Model):
      THICKNESSES = (
          (0, 'thin'),
          (1, 'thick'),
          (3, 'deep dish'),
      )
  
      name = models.CharField(max_length=50)
      price = models.DecimalField(null=True, decimal_places=2, max_digits=4)
      gluten_free = models.BooleanField(default=False)
      description = models.TextField(blank=True)
      thickness = models.CharField(max_length=50, choices=THICKNESSES)
  
      chef = models.ForeignKey(Chef)
  
new_contents: from django.db import models
  
  
  class Chef(models.Model):
      first_name = models.CharField(max_length=60)
      last_name = models.CharField(max_length=60)
  
  
  class Pizza(models.Model):
      THICKNESSES = (
          (0, 'thin'),
          (1, 'thick'),
          (2, 'deep dish'),
      )
  
      name = models.CharField(max_length=50)
      price = models.DecimalField(null=True, decimal_places=2, max_digits=4)
      gluten_free = models.BooleanField(default=False)
      description = models.TextField(blank=True)
      thickness = models.CharField(max_length=50, choices=THICKNESSES)
  
      chef = models.ForeignKey(Chef)
  
subject: fix typo