old_contents: from django.db import models
  
  class MailgunLog(models.Model):
      log_hash = models.CharField(max_length=64, unique=True)
      data = models.TextField()
      timestamp = models.DateTime()
  
new_contents: from django.db import models
  
  class MailgunLog(models.Model):
      log_hash = models.CharField(max_length=64, unique=True)
      data = models.TextField()
      timestamp = models.DateTimeField()
  
subject: Fix incorrect models field name for MailgunLog