Illustrating one of the chapter's insets, the following example shows how a loop uses the next() method and finishes by exception, which occurs when the generator is exhuasted.
| g = (c for c in "fast") |
| length = 0 |
| while True: |
| try: |
| letter = g.next() |
| length += 1 |
| except StopIteration: |
| break |
| print "Length is", length |