I needed to add some sort of date ranging filter into my query. To do that, we first calculate the date range.
six_months_ago = (datetime.date.today() - datetime.timedelta(6 * 365 / 12))
This simply figures out the date which was 6 months from today.
To use that to filter a date field (without time information):
SomeModel.objects.filter(create_date__gte = six_months_ago.isoformat())
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