def pairwise(iterable):
    """
    break a list (or other iterable) into pairs
    
    ::
    
		s -> (s0, s1), (s2, s3), (s4, s5), ...
		
		In [71]: for item in pairwise("a b c d e fg".split()): 
			...:     print(item) 
			...:                                                                                                                         
		('a', 'b')
		('c', 'd')
		('e', 'fg')
  
    """
    a = iter(iterable)
    return zip(a, a)
