python中如何实现列表与集合相互转换？

li=["hello",1,1+3j,1,"2","3","2",3]

print type(li)

s=set(li)

print s

print type(s)

#数组==》集合

lst=list((1,2,3,4));

print(lst)

#map--》集合

lst2=list({"name":"liu","age:":12}.items());

print(lst2)

[1, 2, 3, 4]

[('name', 'liu'), ('age:', 12)]