(l)
return [(l[i-1], v) for i, v in enumerate(l) if i > 0]
Return subsequent pairs of values in a list <l>, i.e. [(x1, x2), (x2, x3), (x3, x4), .. (xn-1, xn)] for a
    list [x1 .. xn]
Return subsequent pairs of values in a list <l>, i.e. [(x1, x2), (x2, x3), (x3, x4), .. (xn-1, xn)] for a
    list [x1 .. xn]
Return subsequent pairs of values in a list <l > i . e . [ ( x1 x2 ) ( x2 x3 ) ( x3 x4 ) .. ( xn - 1 xn ) ] for a list [ x1 .. xn ]
def subsequent_pairs(l):
    """
    Return subsequent pairs of values in a list <l>, i.e. [(x1, x2), (x2, x3), (x3, x4), .. (xn-1, xn)] for a
    list [x1 .. xn]
    """
    
    return [(l[i-1], v) for i, v in enumerate(l) if i > 0]
def subsequent_pairs ( l ) : return [ ( l [ i - 1 ] , v ) for i , v in enumerate ( l ) if i > 0 ]