A = range(1,10)
B = range(5,15)
C =range(8,20)

# A并B并c

result2 = list(set(A).intersection(set(B)).intersection(set(C)))
print(result2)


# AUBUC 并集
result3 = list(set(A).union(set(B).union(C)))
print(result3)

# 差集
# 元素在 A not  B
result4 = list(set(A).difference(set(B)))
print(result4)