https://docs.djangoproject.com/en/dev/topics/signing/#django.core.signing.Signer
from datetime import timedelta
from django.core.signing import TimestampSigner
signer = TimestampSigner()
value = signer.sign('hello')
value
signer.unsign(value)
signer.unsign(value, max_age=10)
signer.unsign(value, max_age=20)
signer.unsign(value, max_age=timedelta(seconds=20))