def two_finger(iterable):
"""
>>> sequence = [1, 3, 9, 5, 22, 11]
>>> for item, next in two_finger(sequence):
... print item, next
...
1 3
3 9
9 5
5 22
22 11
"""
iterator = iter(iterable)
item = iterator.next()
while True:
try:
next = iterator.next()
yield item, next
item = next
except StopIteration:
return