tuple([ (tuple(lst[x-1:x+1]) if len(tuple(lst[x-1:x+1]))==2 else lst[x-1]) for x in lst[::2]])
((1, 2), (3, 4), 5) # or x = ((tuple(lst[x-1:x+1]) if len(tuple(lst[x-1:x+1]))==2 else lst[x-1]) for x in lst[::2]) x.next() (1, 2) x.next() (3, 4) x.next() 5 -- http://mail.python.org/mailman/listinfo/python-list
