Sort Moodle Groups

import csv
import os
import shutil
import errno
import sys

pre = "./"
if (len(sys.argv)<2):
    print("Execute in folder with groups. CSV as comand line parameter.")
    sys.exit()
inputcsv = sys.argv[1]

ls = os.listdir(pre)
ls.sort()
order = dict()
members = dict()

with open(inputcsv, newline='') as csvfile:

    list = csv.reader(csvfile, delimiter=',', quotechar='"')
    firstline = next(list)

    for x in ls:
        order[x] = []
        membersfile = pre + "/" + x + "/" + "members.csv"
        with open(membersfile, 'w', newline='\n') as csvfile:
            csvfile = csv.writer(csvfile, delimiter=',', quotechar='"', quoting=csv.QUOTE_MINIMAL)
            csvfile.writerow(firstline)

    for row in list:
        old = []
        new = []
        groups = row[3].split(", ")
        for group in groups:
            if group in ls:
                old.append(group)
                membersfile = pre + "/" + group + "/" + "members.csv"
                with open(membersfile, 'a', newline='\n') as csvfile:
                    csvfile = csv.writer(csvfile, delimiter=',', quotechar='"', quoting=csv.QUOTE_MINIMAL)
                    csvfile.writerow(row)
            else:
                new.append(group)
        for o in old:
            for n in new:
                if n not in order[o]:
                    order[o].append(n)

for x in order:
    for y in order[x]:
        src = pre + "/" + x
        dst = pre + "/" + y
        if not os.path.exists(dst):
            os.mkdir(dst)
        os.symlink("../" + x, dst + "/" + x)