import sys
#the following tests for the presence of libraries 
#and complains if they are not available
try:
  from OpenGL.GLUT import *
  from OpenGL.GL import *
  from OpenGL.GLU import *
except:
  print '''
  ERROR: PyOpenGL is not installed. 
        '''
  sys.exit()

from math import *

#note, there are preciously few classes defined and used 
#my clocker seems to be "unique" in that its instances do
#something when called, rather than passively collecting
#variables and methods (functions).