Use set.pop
:
>>> {1}.pop()
1
>>>
In your case, it would be:
return S.pop()
Note however that this will remove the item from the set. If this is undesirable, you can use min
|max
:
return min(S) # 'max' would also work here
Demo:
>>> S = {1}
>>> min(S)
1
>>> S
set([1])
>>> max(S)
1
>>> S
set([1])
>>>