Generate time options for different timezones

timezone_options.py

from datetime import datetime, date, time, timedelta
from pytz import timezone

START_DATE = date(2017, 10, 9)
START_TIME = time(8, 0)
START_DATETIME = datetime.combine(START_DATE, START_TIME)

INTERVAL_IN_HOURS = 2
OPTION_TEMPLATE = "{start} - {end} ({tz})"

eastern = timezone('US/Eastern')
pacific = timezone('US/Pacific')
london = timezone('Europe/London')

start_eastern_dt = START_DATETIME.replace(tzinfo=eastern)
current_eastern_dt = start_eastern_dt


def get_option(start_dt, end_dt, original_tz, new_tz):
    start = start_dt
    end = end_dt
    if original_tz != new_tz:
        start = start_dt.astimezone(new_tz)
        end = end_dt.astimezone(new_tz)

    option = OPTION_TEMPLATE.format(
        start=start.strftime("%I%p"),
        end=end.strftime("%I%p"),
        tz=new_tz.zone.split('/')[1])
    return option


def print_intervals_in_tzs(
        original_tz, timezones, start_dt, interval_in_hours, options_count):
    current_dt = start_dt

    for _ in range(options_count):
        start = current_dt
        end = current_dt + timedelta(hours=interval_in_hours)

        options = [get_option(start, end, original_tz, tz) for tz in timezones]

        print(" | ".join(options))
        current_dt = end


if __name__ == '__main__':
    print_intervals_in_tzs(
        eastern,
        timezones=[eastern, pacific, london],
        start_dt=start_eastern_dt,
        interval_in_hours=INTERVAL_IN_HOURS,
        options_count=7)

Output:

08AM - 10AM (Eastern) | 05AM - 07AM (Pacific) | 01PM - 03PM (London)
10AM - 12PM (Eastern) | 07AM - 09AM (Pacific) | 03PM - 05PM (London)
12PM - 02PM (Eastern) | 09AM - 11AM (Pacific) | 05PM - 07PM (London)
02PM - 04PM (Eastern) | 11AM - 01PM (Pacific) | 07PM - 09PM (London)
04PM - 06PM (Eastern) | 01PM - 03PM (Pacific) | 09PM - 11PM (London)
06PM - 08PM (Eastern) | 03PM - 05PM (Pacific) | 11PM - 01AM (London)
08PM - 10PM (Eastern) | 05PM - 07PM (Pacific) | 01AM - 03AM (London)