pipeline.py

#!/usr/bin/env python

def remove_a(values):
    for value in values:
        new_value = value.replace('a', '')
        print 'remove a'
        yield new_value

def remove_b(values):
    for value in values:
       new_value = value.replace('b', '')
       print 'removed b'
       yield new_value

def remove_c(values):
    for value in values:
        new_value = value.replace('c', '')
        print 'removed c'
        yield new_value

def pipeline(_file):
    chain = remove_c(remove_b(remove_a(open(_file))))
    return chain

def generator():
    answer = (yield)
    if answer == 'stupid':
        kill()
    try:
        anything()
    except ValueError:
        other()
    finally:
        cleanup()



g = generator()
g.send(fgsdfg)
g.throw(ValueError)
g.close()

threading.Thread()
multitask