The wxPython GUI toolkit has a nice numeric LED widget (LEDNumberCtrl from the wx.gizmos module) that is used here for displaying the current time in very visible 7 segment LED color display. It also shows the application of the time module and wx.Timer(). The code is simple as far as GUI code goes, and commented so you can study it.

# use the wxPython LEDNumberCtrl widget for nice LED clock
# Python25 and wxPython28   by  HAB     07/30/2007

import time
import wx
import wx.gizmos as gizmos

class LED_clock(wx.Frame):
    create nice LED clock showing the current time
    def __init__(self, parent, id):
        pos = wx.DefaultPosition
        wx.Frame.__init__(self, parent, id, title='LED Clock', pos=pos, size=(350, 100))
        size = wx.DefaultSize
        style = gizmos.LED_ALIGN_CENTER
        self.led = gizmos.LEDNumberCtrl(self, -1, pos, size, style)
        # default colours are green on black
        self.timer = wx.Timer(self, -1)
        # update clock digits every second (1000ms)
        self.Bind(wx.EVT_TIMER, self.OnTimer)

    def OnTimer(self, event):
        # get current time from computer
        current = time.localtime(time.time())
        # time string can have characters 0..9, -, period, or space
        ts = time.strftime("%H %M %S", current)

# test the clock ...
if __name__ == '__main__':
    app = wx.App()
    frame = LED_clock(None, -1)