How to annotate with F()?

[ivlevdenis]

        datebased_prices = (
            BasePrice.objects.instance_of(DateBasedPrice)
            .filter(car=car, DateBasedPrice___range__overlap=DateRange(range.lower.date(), range.upper.date()))
            .annotate(range_overlap=F('DateBasedPrice___range'))
            
        )

        datetimebased_prices = (
            BasePrice.objects.instance_of(DateTimeBasedPrice)
            .filter(car=car, DateTimeBasedPrice___range__overlap=range)
            .annotate(range_overlap=F('DateTimeBasedPrice___range'))
        )

        prices = (datebased_prices | datetimebased_prices)

all times return None in range_overlap