Pyton 获取两个 list 的差集、并集

求差：

1. method one:
   

   list_one = [1, 2, 3]
   listd_two = [2, 3]
   diff = []
   for  x in list_one:
       if x not in list_two:
           diff.append(x)

   
   
2. method two:

   diff = [x for x in list_one if x not in list_two]

   
   
3. method three:

   diff = list(set(list_one)^set(list_two))

   
   
4. method four:

   diff = list(set(list_one).difference(set(list_two))) one中有而two中没有的

   
   

求和：

tt = list(set(list_one).union(set(list_two)))

求交：

for x in list_one:
    if x in list_two:
        jj.append(x)