新手python刚刚上路，在实际工作中遇到如题所示的问题，尝试使用python3简单实现如下，欢迎高手前来优化

import csv

#打开文件，用with打开可以不用去特意关闭file了，python3不支持file()打开文件，只能用open()

with open("dk0519_1.csv","r",encoding="utf-8") as csv_file:

     #读取csv文件，返回的是迭代类型

    read = csv.reader(csv_file)

    alist = []

    bdict = []

    cdict = []

    tmp = []

    for i in read:

        alist.append(i[0].split("\t"))

    for a in alist[1:]:

        print(a)

        bdict.append((a[0].split("?")[0],a[1]))

    for b in bdict:

        num = int(b[1])

        j = bdict.index(b) + 1

        while j <= (len(bdict)-1) :

            if b[0] not in tmp:

                if b[0] == bdict[j][0]:

                    num += int(bdict[j][1])

                    j += 1

                else:

                    j +=1

            else:

                j +=1

        if b[0] not in tmp:

            cdict.append((b[0],num))

        else:

            pass

        tmp.append(b[0])

with open('re_dk0519_1.csv','w',encoding="utf-8") as write_csvfile:

    writer = csv.writer(write_csvfile)

    writer.writerows(cdict)