>>> test1 = ["aaa","bbb","ccc","ddd","eee","fff"]
>>> test2 = ["ddd","eee","fff","ggg","hhh","iii"]
>>> test3 = test1 + test2
>>> test3
['aaa', 'bbb', 'ccc', 'ddd', 'eee', 'fff', 'ddd', 'eee', 'fff', 'ggg', 'hhh', 'iii']
>>> test4 = []
>>> for i in test3: ## 求交集
if i not in test4:
test4.append(i)
>>> test4
['aaa', 'bbb', 'ccc', 'ddd', 'eee', 'fff', 'ggg', 'hhh', 'iii']
>>> test5 = []
>>> for i in test1: ## 求并集
if i in test2:
test5.append(i)
>>> test5
['ddd', 'eee', 'fff']
>>> test6 = []
>>> for i in test1: ## 求单侧并集
if i not in test2:
test6.append(i)
>>> test6
['aaa', 'bbb', 'ccc']