@classmethod
    def _cache_key(cls, pk, db):
        key_parts = ('o', cls._meta, pk, 'default')
        return ':'.join(map(encoding.smart_unicode, key_parts))
Returns a Python `datetime` object for this OFTDateTime field.
dataset/ETHPy150Open mozilla/addons-server/src/olympia/amo/models.py/ModelBase._cache_key--crossover with--dataset/ETHPy150Open AppScale/appscale/AppServer/lib/django-1.5/django/contrib/gis/gdal/field.py/OFTDateTime.value