within_last query.py

DAY, WEEK, MONTH, YEAR = map(timedelta, (1, 7, 30, 365))


def newer_than(fieldname, delta)
    # positive values go to past, negative to future. counterintuitive?
    time = datetime.now() - delta
    fieldname = fieldname + "__gte"
    return Q(**fieldname: past)

# For more granularity. Probably YAGNI
def newer_than2(fieldname, **delta_args)
    return newer_than(fieldname, timedelta(**delta_args))

# example
Blog.objects.filter(newer_than('created', 2*WEEKS))