Sets

s1 = set([1,1,1,2,3])
print(s1)

# {1, 2, 3}

• add()

s2 = set()
s2.add(1)

#{1}

• clear()

s3 = {1,2,3}
s3.clear()

#set()

• copy() —— copy by reference

• discard()

  s2.add(2)
  s2.discard(1)
  
  #{2}
  

Sets

• difference()
• intersection()
• union()

a.different(b) # A - B
b.different(a) # B - A
a.intersection() = b.intersection() #{3, 4}
a.union = b.union #{1,3,4,5,7,8}

• isdisjoint()

• issubset()
• issuperset()