How to distribute work to a set of worker threads in Python?

import threading, queue, time

# The worker thread gets jobs off the queue. When the queue is empty, it
# assumes there will be no more work and exits.
def worker():
   print('Running worker')
   time.sleep(0.1)
   while True:
      try:
         arg = q.get(block=False)
      except queue.Empty:
         print('Worker', threading.current_thread(), end=' ')
         print('queue empty')
         break
      else:
         print('Worker', threading.current_thread(), end=' ')
         print('running with argument', arg)
         time.sleep(0.5)

# Create a queue
q = queue.Queue()

# Start a pool of 5 workers
for i in range(5):
   t = threading.Thread(target=worker, name='worker %i' % (i+1))
   t.start()

# Begin adding work to the queue
for i in range(50):
   q.put(i)

# Give threads time to run
print('Main thread sleeping')
time.sleep(5)

Running worker
Running worker
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Main thread sleeping
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