def generateItems(seq):
    for item in seq:
        yield 'item: %s' % item

anIter = generateItems([])
print 'dir(anIter):', dir(anIter)
anIter = generateItems([111,222,333])
for x in anIter:
    print x
anIter = generateItems(['aaa', 'bbb', 'ccc'])
print anIter.next()
print anIter.next()
print anIter.next()
print anIter.next()