A simple clock using Tkinter

clock.py

from time import strftime
import Tkinter


numbers = {0:'midnight',
           1:'one',
           2:'two',
           3:'three',
           4:'four',
           5:'five',
           6:'six',
           7:'seven',
           8:'eight',
           9:'nine',
           10:'ten',
           11:'eleven',
           12:'twelve',
           15:'quarter',
           20:'twenty',
           25:'twenty and five',
           30:'half'}


def get_hour(h):
    if h > 12:
        h -= 12
    return numbers[h]


def get_minute(m):

    if m in (58, 59, 0, 1, 2):
        return ''

    m = int((m + 2.5) / 5) * 5

    if m <= 30:
        prefix = 'past'
    else:
        m = 60 - m
        prefix = 'to'

    return "%s %s" % (numbers[m], prefix)


def get_time(h,m):

    minute = get_minute(m)

    if m >= 33:
        h += 1

    hour = get_hour(h)

    if minute:
        return "%s %s" % (minute, hour)
    elif hour == 'midnight':
        return hour
    else:
        return "%s o' clock" % get_hour(h)


class Clock(object):

    def __init__(self, root):
        self.clock = Tkinter.Label(master=root)
        self.clock['font'] = 'Helvetica 44 bold'
        self.clock.pack()
        self._tictac()

    def _tictac(self):
        h,m = map(int, strftime("%H %M").split())
        now = get_time(h,m)
        if self.clock['text'] != now:
            self.clock['text'] = now
        self.clock.after(1000, self._tictac)


if __name__ == '__main__':
    root = Tkinter.Tk()
    c = Clock(root)
    root.mainloop()