def reverse_enumerate(l):
    """Like enumerate but in the other direction

    Usage::
    >>> a = ['a', 'b', 'c']
    >>> it = reverse_enumerate(a)
    >>> it.next()
    (2, 'c')
    >>> it.next()
    (1, 'b')
    >>> it.next()
    (0, 'a')
    >>> it.next()
    Traceback (most recent call last):
      File "<stdin>", line 1, in <module>
    StopIteration
    """
    return zip(range(len(l)-1, -1, -1), reversed(l))