old_contents: #! /usr/bin/env python
  
  # Print digits of pi forever.
  #
  # The algorithm, using Python's 'long' integers ("bignums"), works
  # with continued fractions, and was conceived by Lambert Meertens.
  #
  # See also the ABC Programmer's Handbook, by Geurts, Meertens & Pemberton,
  # published by Prentice-Hall (UK) Ltd., 1990.
  
  import sys
  
  def main():
      k, a, b, a1, b1 = 2L, 4L, 1L, 12L, 4L
      while 1:
          # Next approximation
          p, q, k = k*k, 2L*k+1L, k+1L
          a, b, a1, b1 = a1, b1, p*a+q*a1, p*b+q*b1
          # Print common digits
          d, d1 = a//b, a1//b1
          while d == d1:
              output(d)
              a, a1 = 10L*(a%b), 10L*(a1%b1)
              d, d1 = a//b, a1//b1
  
  def output(d):
      # Use write() to avoid spaces between the digits
      # Use str() to avoid the 'L'
      sys.stdout.write(str(d))
      # Flush so the output is seen immediately
      sys.stdout.flush()
  
  if __name__ == "__main__":
      main()
  
new_contents: #! /usr/bin/env python
  
  # Print digits of pi forever.
  #
  # The algorithm, using Python's 'long' integers ("bignums"), works
  # with continued fractions, and was conceived by Lambert Meertens.
  #
  # See also the ABC Programmer's Handbook, by Geurts, Meertens & Pemberton,
  # published by Prentice-Hall (UK) Ltd., 1990.
  
  import sys
  
  def main():
      k, a, b, a1, b1 = 2, 4, 1, 12, 4
      while True:
          # Next approximation
          p, q, k = k*k, 2*k+1, k+1
          a, b, a1, b1 = a1, b1, p*a+q*a1, p*b+q*b1
          # Print common digits
          d, d1 = a//b, a1//b1
          while d == d1:
              output(d)
              a, a1 = 10*(a%b), 10*(a1%b1)
              d, d1 = a//b, a1//b1
  
  def output(d):
      # Use write() to avoid spaces between the digits
      sys.stdout.write(str(d))
      # Flush so the output is seen immediately
      sys.stdout.flush()
  
  if __name__ == "__main__":
      main()
  
subject: Remove unneeded "L" suffixes.