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### why i cannot use intersection with position list

hi guys, i try to find a intersection set of two position lists

so i write a code in python, and i have two lists, such as :

position1 = Point()

position1.x =1

position2 = Point()

position2.x=2

a = [copy.deepcopy(position1),copy.deepcopy(position2)]

b = [copy.deepcopy(position1)]


then, when i try to get intersection of those two list a and b

it return me an answer: set([])

that's ridiculous,

normally i should have an answer like: set(a).intersection(set(b)) = set([position1])

if anyone could help me to fix this problem?

it's great thankful for viewing this problem