old_contents: from django.db import models
  from django.utils import timezone
  
  
  class TaskExecution(models.Model):
      time = models.DateTimeField(default=timezone.now)
      key = models.CharField(max_length=256)
      execution_number = models.IntegerField()
  
      class Meta:
          unique_together = ('key', 'execution_number')
  
      def __unicode__(self):
          return '%s:%s' % (self.key, self.time)
  
new_contents: from django.db import models
  from django.utils import timezone
  
  
  class TaskExecution(models.Model):
      time = models.DateTimeField(default=timezone.now)
      key = models.CharField(max_length=256)
      execution_number = models.IntegerField()
  
      class Meta:
          unique_together = ('key', 'execution_number')
          app_label = 'jitishcron'
  
      def __unicode__(self):
          return '%s:%s' % (self.key, self.time)
  
subject: Add app_label to jitishcron TaskExecution model