
def get_date_range(request):
    """
    Return start_date and end_date from form,
    defaulting to the last 30 days.
    """

    today = date.today()

    start_date = request.form.get(
        "start_date",
        (today - timedelta(days=30)).isoformat()
    )

    end_date = request.form.get(
        "end_date",
        today.isoformat()
    )

    return start_date, end_date

