python中如何比较两个列表不同

#-*- coding:utf-8 -*-
import time

#方法1:
def getDiff1(arr1,arr2):
    start_time = time.time()
    print('1_start:',start_time)
    arr_more1 = []
    arr_more2 = []
    dic_result = {}

    for str_1 in arr1:
        dic_result[str(str_1)] = 1

    for str_2 in arr2:
        if dic_result.get(str(str_2)):
            dic_result[str(str_2)] = 2
        else:
            arr_more2.append(str_2)

    for key,val in dic_result.items():
        if val == 1:
            arr_more1.append(key)

    print('arr1比arr2多的内容为:',len(arr_more1))
    print('arr2比arr1多的内容为:',len(arr_more2))

    end_time = time.time()
    print('1_end:',end_time)
    print('方法1_比对用时为',end_time-start_time)


#方法2:使用集合运算:
def getDiff2(arr1,arr2):
    start_time = time.time()
    print('2_start:',start_time)
    set_1 = ()
    set_2 = ()

    #将列表转换为集合set()
    set_1 = set(arr1)
    set_2 = set(arr2)

    set_more1 = ()
    set_more2 = ()

    #集合运算
    set_1_2 = set_1 & set_2
    set_more1 = set_1 -set_1_2
    set_more2 = set_2 -set_1_2

    print('arr1比arr2多的内容为:',len(set_more1))
    print('arr2比arr1多的内容为:',len(set_more2))

    end_time = time.time()
    print('2_end:',end_time)
    print('方法2_比对用时为',end_time-start_time)

#测试

# 初始化500w条数据数据
arr1 = []
arr2 = []
i = 0
while(True):
    arr1.append(i * 2)
    arr2.append(i * 3)
    i += 1
    if i > 5000000:
        break

print('arr1的长度为:',len(arr1))
print('arr2的长度为:',len(arr2))
print('+'*30)
getDiff1(arr1,arr2)
print('-'*30)
getDiff2(arr1,arr2)