What's the difference between .union and | for sets in python?

Question

What's the difference between .union and | for sets in python?

>>> a = set([1, 2, 3, 4])
>>> b = set([3, 4, 5, 6])

>>> a|b
{1, 2, 3, 4, 5, 6}

>>> a.union(b)
{1, 2, 3, 4, 5, 6}

Answer 1

No difference.

In fact on the official python documentation about sets they are written together.

There is a little difference: one is an operator, so it has specific operator the operator precedence (eg if mixed with other set operators). On the function case, the function parenthesis explicitly fix the priority.