A little timer for international airplane flights

plane_timer.py

import sys
import time
from datetime import datetime, timedelta


START_TIME = datetime(2013, 3, 23, 0, 0, 0, 0)
TRIP_TIME = timedelta(minutes=8.7 * 60)
END_TIME = START_TIME + TRIP_TIME
BAR_WIDTH = 100


while True:
    time_left = END_TIME - datetime.now()
    hours_left = int(time_left.total_seconds() / 3600)
    minutes_left = int((time_left.total_seconds() % 3600) / 60)

    percent_left = time_left.total_seconds() / TRIP_TIME.total_seconds()
    percent_complete = 1 - percent_left

    complete_chars = int(percent_complete * BAR_WIDTH)
    left_chars = BAR_WIDTH - complete_chars

    sys.stdout.write('[{complete_bar}{left_bar}] ({percent_complete}%, {hours}:{mins} left)\r'.format(
        complete_bar='*' * complete_chars,
        left_bar=' ' * left_chars,
        percent_complete=round(100 * percent_complete, 2),
        hours=hours_left,
        mins=('0' if minutes_left < 10 else '') + str(minutes_left),
    ))
    sys.stdout.flush()

    if time_left <= timedelta(0, 0, 0):
        break

    time.sleep(0.1)