Django "Last Modified" and "Created" timestamps as custom field types.

django_timestamp_fields.py

"""
This is a simple implementation of "last modified" and "created" timestamps custom field types for Django.

I used this in a few projects due to talk of deprecating "auto_now" and "auto_now_add" for DateTime fields.
It doesn't seem as necessary now that said options appear to be staying in Django.
That said, I figured I might as well have this snippet just in case.
"""

from django.db import models
from django.utils import timezone


class TimeStampLastModifiedField(models.DateTimeField):
    """
    Custom field for last updated timestamp
    """
    def pre_save(self, model_instance, add):
        return timezone.now()


class TimeStampCreatedField(models.DateTimeField):
    """
    Custom field for create timestamp
    """
    def pre_save(self, model_instance, add):
        if not add:
            return getattr(model_instance, self.attname)
        return timezone.now()