notifications-api/app/dao/date_util.py

from datetime import datetime, timedelta

import pytz


def get_financial_year(year):
    return get_april_fools(year), get_april_fools(year + 1) - timedelta(microseconds=1)


def get_april_fools(year):
    """
     This function converts the start of the financial year April 1, 00:00 as BST (British Standard Time) to UTC,
     the tzinfo is lastly removed from the datetime becasue the database stores the timestamps without timezone.
     :param year: the year to calculate the April 1, 00:00 BST for
     :return: the datetime of April 1 for the given year, for example 2016 = 2016-03-31 23:00:00
    """
    return pytz.timezone('Europe/London').localize(datetime(year, 4, 1, 0, 0, 0)).astimezone(pytz.UTC).replace(
        tzinfo=None)