[Tutor] how to invert tuples

[Laura Creighton]

In a message of Sun, 22 Nov 2015 21:58:35 +0100, marcus lütolf writes:
>dear pythonistas
>
>i have written the code below for identifying tuples occurring twice or more times in the list of tuples called "flights".
>1. Question: How can i modify this code so it does not matter which string is first and which is second  or (h,i) == (i,h) respectively ?

This may be an indication that you have got the wrong datatype.  It may be
that you would be happier with a set.

 >>> s1={'Stockholm', 'Berlin'}
 >>> s2={'Berlin', 'Stockholm'}
 >>> s1 == s2
True

If you need a tuple later -- for instance you want to use the tuple as a
key in a dictionary later, because you cannot use the set directly

 >>> tuple(s1)
('Stockholm', 'Berlin')
 >>> tuple(s2)
('Stockholm', 'Berlin')
 >>> 

Laura