import
itertools
for
i
in
itertools.permutations(
'xyz'
):
if
i[
0
] !
=
'x'
and
i[
2
] !
=
'x'
and
i[
2
] !
=
'z'
:
print
(
'a vs %s, b vs %s, c vs %s'
%
(i[
0
], i[
1
], i[
2
]))