from django.db import models

class TimeStampedModel(models.Model):
    """
    An abstract base class model that provides selfupdating ``created`` and ``modified`` fields.
    """
    created = models.DateTimeField(auto_now_add=True)
    modified = models.DateTimeField(auto_now=True)
    class Meta:
        abstract = True
Add core models(TimeStampedModel) for all models