text: 
  import math
  import sys
  import ppft
  
  LOCAL_WORKERS = 'autodetect' #XXX: 'autodetect' or 0,1,2,...
  
  def isprime(n):
      """Returns True if n is prime and False otherwise"""
      if not isinstance(n, int):
          raise TypeError("argument passed to is_prime is not of 'int' type")
      if n < 2:
          return False
      if n == 2:
          return True
      max = int(math.ceil(math.sqrt(n)))
      i = 2
      while i <= max:
          if n % i == 0:
              return False
          i += 1
      return True
  
  def sum_primes(n):
      """Calculates sum of all primes below given integer n"""
      return sum([x for x in range(2, n) if isprime(x)])
  
  ########################################################################
  
  print("""Usage: python sum_primesX.py [tunnelport]
      [tunnelport] - the port number(s) of the local ssh tunnel connection,
      if omitted no tunneling will be used.""")
  
  ppservers = []
  for i in range(1,len(sys.argv)):
      tunnelport = int(sys.argv[i])
      ppservers.append("localhost:%s" % tunnelport)
  ppservers = tuple(ppservers)
  
  # Creates jobserver with automatically detected number of workers
  job_server = ppft.Server(ppservers=ppservers)
  
  # Allow running without local workers
  if LOCAL_WORKERS != 'autodetect':
      job_server.set_ncpus(LOCAL_WORKERS)
  
  #print("Known servers: [('local',)] %s %s" % (job_server.ppservers,job_server.auto_ppservers))
  print("Known servers: [('local',)] %s" % (job_server.ppservers))
  print("Starting ppft with %s local workers" % job_server.get_ncpus())
  
  # Submit a job of calulating sum_primes(100) for execution.
  # sum_primes - the function
  # (100,) - tuple with arguments for sum_primes
  # (isprime,) - tuple with functions on which function sum_primes depends
  # ("math",) - tuple with module names which must be imported before
  #             sum_primes execution
  # Execution starts as soon as one of the workers will become available
  ###job1 = job_server.submit(sum_primes, (100, ), (isprime, ), ("math", ))
  
  # Retrieves the result calculated by job1
  # The value of job1() is the same as sum_primes(100)
  # If the job has not been finished yet, execution will
  # wait here until result is available
  ###result = job1()
  
  ###print("Sum of primes below 100 is %s" % result)
  
  
  # The following submits 8 jobs and then retrieves the results
  inputs = (100000, 100100, 100200, 100300, 100400, 100500, 100600, 100700)
  print(inputs)
  
  jobs = [(input, job_server.submit(sum_primes, (input, ), (isprime, ),
          ("math", ))) for input in inputs]
  
  for input, job in jobs:
      print("Sum of primes below %s is %s" % (input, job()))
  
  job_server.print_stats()
  