Django humanized time since filter

hts.py

#!/usr/bin/env python
# -*- coding: utf-8 -*-
from datetime import datetime, timedelta

from django.template.defaultfilters import date, timesince
from django.template import Library
from django.utils.translation import ugettext


register = Library()

@register.filter('humanized_timesince')
def humanized_timesince_filter(value, arg=None):
    """Humanized time since filter.

    - Within the hour: `1 minute` to `59 minutes`
    - Within the day: `1 hour` to `23 hours`
    - Within 48 hours and after a day: `yesterday`
    - Within the week, after 48 hours: Day of the week
    - After a week: default `timesince` functionality

    >>> tnow = datetime(2012, 10, 9, 0, 0, 0 , 0)
    >>> datetime.strftime(tnow, '%A')
    'Tuesday'
    >>> humanized_timesince_filter(datetime(2012, 10, 8, 23, 59, 0, 0), tnow)
    u'1 minute'
    >>> humanized_timesince_filter(datetime(2012, 10, 8, 23, 1, 0, 0), tnow)
    u'59 minutes'
    >>> humanized_timesince_filter(datetime(2012, 10, 8, 23, 0, 0, 0), tnow)
    u'1 hour'
    >>> humanized_timesince_filter(datetime(2012, 10, 8, 1, 0, 0, 0), tnow)
    u'23 hours'
    >>> humanized_timesince_filter(datetime(2012, 10, 8, 0, 0, 0, 0), tnow)
    u'yesterday'
    >>> humanized_timesince_filter(datetime(2012, 10, 7, 0, 0, 0, 0), tnow)
    u'Sunday'
    >>> humanized_timesince_filter(datetime(2012, 10, 3, 0, 0, 0, 0), tnow)
    u'Wednesday'
    >>> humanized_timesince_filter(datetime(2012, 10, 2, 0, 0, 0, 0), tnow)
    u'1 week'
    >>> humanized_timesince_filter(datetime(2012, 9, 9, 0, 0, 0, 0), tnow)
    u'1 month'
    >>> humanized_timesince_filter(datetime(2012, 8, 9, 0, 0, 0, 0), tnow)
    u'2 months'
    >>> humanized_timesince_filter(datetime(2012, 7, 21, 1, 0, 0, 0), tnow)
    u'2 months, 2 weeks'
    >>> humanized_timesince_filter(datetime(2011, 10, 1, 0, 0, 0, 0), tnow)
    u'1 year'
    >>> humanized_timesince_filter(datetime(2011, 6, 1, 0, 0, 0, 0), tnow)
    u'1 year, 4 months'

    """
    if not value:
        return u''

    compare_to = type(arg) == datetime and arg or datetime.now()
    one_day = compare_to - timedelta(hours=24)
    two_days = compare_to - timedelta(hours=48)
    week = compare_to - timedelta(days=7)

    func, args = timesince, (value, compare_to)
    if one_day < value < compare_to:
        args = (value, compare_to)
    elif two_days < value < compare_to:
        return ugettext('yesterday')
    elif week < value < compare_to:
        func = date
        args = (value, 'l')
    return func(*args)

if __name__ == "__main__":
    import doctest
    doctest.testmod()