The parallel Python library provides a set of functions for simple distributed computation. It uses the ZeroMQ socket library for reliable data transport across any size of network.

import parallel

# list containing (ventilator, sink) address pairs
worker_addresses = [('localhost:5000', 'localhost:5001'), ('10.0.1.34:5000', '10.0.1.34:5001')]
# construct functions to control parallel processing
worker, close, run_job = parallel.construct_worker(worker_addresses)

# job function
def sample_job(num):
    return num + 3

# called when a job is done processing
def on_recv_result(result, job_info, args):
    print 'Job #', job_info.job_id, ' returned the result: ', result

# run lots of jobs
for num in range(100):
    run_job(sample_job, (num,))

# send jobs, pull and process jobs, and handle completed jobs
worker(on_recv_result, ())

Workers are constructed and run on two different machines with parallel.construct_worker() and the returned worker() function. Another worker is constructed on a third machine. After (or before) the worker() function is called jobs are added to the queue with run_job(). Because there are three workers, the third worker sends the first three jobs and waits for replies. All three of the workers are watching for jobs and they each grab one of the first three jobs. When one finishes processing the job it sends back the result. The third worker receives the result and sends out another job.