class Set:
def init(self):
self.elements = []

def add(self, newElement):
    if newElement not in self.elements:
        self.elements.append(newElement)

def remove(self, element):
    if element in self.elements:
        self.elements.remove(element)

def contains(self, element):
    return element in self.elements

def size(self):
    return len(self.elements)

def iterator(self):
    return iter(self.elements)

def intersection(self, otherSet):
    intersectionSet = Set()
    for element in self.elements:
        if otherSet.contains(element):
            intersectionSet.add(element)
    return intersectionSet

def union(self, otherSet):
    unionSet = Set()
    unionSet.elements = self.elements.copy()
    for element in otherSet.elements:
        unionSet.add(element)
    return unionSet

def difference(self, otherSet):
    differenceSet = Set()
    for element in self.elements:
        if not otherSet.contains(element):
            differenceSet.add(element)
    return differenceSet

def subset(self, otherSet):
    for element in self.elements:
        if not otherSet.contains(element):
            return False
    return True

Example usage

set1 = Set()
set1.add(1)
set1.add(2)
set1.add(3)

set2 = Set()
set2.add(3)
set2.add(4)
set2.add(5)

print("Set 1:", list(set1.iterator()))
print("Set 2:", list(set2.iterator()))

print("Intersection:", list(set1.intersection(set2).iterator()))
print("Union:", list(set1.union(set2).iterator()))
print("Difference (Set 1 - Set 2):", list(set1.difference(set2).iterator()))

print("Set 1 is a subset of Set 2:", set1.subset(set2))