Updated "short example" for Python 3

xrange() doesn't exist in Python3, but range() exists in Python 2.6, 2.7, and 3.3. Likewise, map() is lazy in Python 3, so you need to force its evaluation in this kind of situation where you actually want to trigger all of the side-effects (e.g. instantiating TaskGenerators.)
Merge pull request #13 from abingham/patch-1

Updated "short example" for Python 3