In the code you copied over from my public/cs21/week06 is a file randomOps.py, that contain examples of using the random library.

To use the random library, you need to import it. At the top of your program:

from random import *

You can also run help(random) in the python interpreter to see which functions the random library provides:

$ python
>>> import random
>>> help(random)

The code in randomOps.py contains examples of how to use the most useful functions in this library:

random():                get the next random number in the range [0.0, 1.0)
randrange(start, stop):  get the next random number in the range [start, stop)
randrange(stop):         get the next random number in the range [0, stop)

randomOps.py:

"""
   Some sample code illustrating use of random library
   Author: Andrew Danner
   Date: October 2008
"""

from random import *

def coinFlip():
  """
    Flip a coin randomly and return 'H' for heads or 'T' for tails
      returns: 'H' for heads or 'T' for tails
  """
  if randrange(2)==0:
    return 'H'
  return 'T'

############################################################
def main():

  #get a list of 5 random ints between 0 and 9 (inclusive)
  l=[]
  for i in range(5):
    rnum=randrange(10)
    l.append(rnum)
  print l

  #get a list of 3 random floats between 0 and 1
  flist=[]
  for i in range(3):
    rfloat=random()
    flist.append(rfloat)
  print flist

  #flip a coin 4 times
  for i in range(4):
    print coinFlip(),
  print

main()