$ python2.6>>> mylist = [20, 30, 25, 20]>>> {x for x in mylist if mylist.count(x) >= 2} File "<stdin>", line 1 {x for x in mylist if mylist.count(x) >= 2} ^SyntaxError: invalid syntax$ python2.7>>> mylist = [20, 30, 25, 20]>>> {x for x in mylist if mylist.count(x) >= 2}set([20])您可以使用显式
set和来在python2.6中完成结果
generator：
>>> set(x for x in mylist if mylist.count(x) >= 2)set([20])
