list append not working correctly

有一个代码用于填充 IP 地址范围，使其没有重叠。

• 先前的版本运行良好，但为了使其自动化并减少资源占用，代码进行了更改。
• 目前代码的输出结果与预期不符

2. 解决方案

• 问题出在对 SubOut1 列表的赋值方式上。
• 在原代码中，使用 subwr=line3 将 line3 直接赋值给 subwr，导致对 SubOut1 中的元素进行修改时，也会影响到 line3 中的原始数据。
• 修改后的代码使用 subwr = line3.copy() 将 line3 的副本赋值给 subwr，这样对 SubOut1 中的元素进行修改时，不会影响到 line3 中的原始数据。

代码示例：

import ipaddress
import csv
from csv import DictReader, DictWriter
import cProfile
import pstats
import operator
import time

start_time=time.strftime("%I:%M:%S %p", time.localtime())


alphlst=[]
SubnetDic1=[]
global SubnetDic2

with open(r'C:\ExampleBefore.csv', newline='') as fin:

    read = DictReader(fin)

    for line in read:
        alphlst.append(line)



def program():
    print("started")
    global alphlst
    lst3=[]
    global lst4
    lst4=[]
    global lst5
    lst5=[]
    endlist=[]
    global SubnetDic1
    SubnetDic1=[]
    global SubnetDic2
    SubnetDic2=[]
    global SubOut1
    SubOut1=[]
    global SubOut2
    SubOut2=[]
    msklst=[]
    global lst
    lst=[]

    print(alphlst)

    print("^ alphlst")


    for li in alphlst:
        li['CIDR']=ipaddress.ip_network(li['CIDR'])
        SubnetDic2.append(li)
        if str(li['CIDR'].netmask) != '255.255.255.255':
            SubnetDic1.append(li)

    print("alph list clear")


    alphlst=[]

    print("after alph list clear")


    print("Dic lists completed")

    def Overlap(y, z):

        global lst5
        global lst

        try:
            if y['CIDR'].overlaps(z['CIDR']):
                lst=list(y['CIDR'].address_exclude(z['CIDR'])) # List of subnets excluding line4 subnet
                if len(lst) != 0:
                    print("not empty. {} is obsolete.".format(y['CIDR']))
                    lst5.append(str(y['CIDR']))
                    print(lst)
        except ValueError:
            return False





    for line3 in SubnetDic1:
        line3['CIDR']=ipaddress.ip_network(line3['CIDR']) # Convert IP ranges to ip network object
        lst3.append(str(line3['CIDR']))
        for line4 in SubnetDic2:
            line4['CIDR']=ipaddress.ip_network(line4['CIDR']) # Convert IP ranges to ip network object
            Overlap(line3, line4) # Tests for IP overlap
            for val in lst:
                if str(val) not in lst3:
                    if str(val) not in lst4:
                        subwr=line3.copy() # Create a copy of line3
                        subwr['CIDR']=val # New range
                        subwr['IPStart']=val.network_address #New net address
                        subwr['IPStop']=val.broadcast_address #New broadcast address
                        SubOut1.append(subwr)
                        print("{} is line3".format(subwr))
                        print("{} is line3 tst".format(line3))
                        lst4.append(str(val))



    print(SubOut1)
    print("^ SubOut1")




    print("Subnet part1 completed")

    global lst7


    lst7=[]


    for line5 in SubnetDic2:
        line5['CIDR']=ipaddress.ip_network(line5['CIDR']) # Convert IP ranges to ip network object
        lst7.append(str(line5['CIDR']))
        print("{} line5 end".format(line5))
        if str(line5['CIDR']) not in lst5:
            print("{} line5 aft".format(line5))
            SubOut2.append(line5) # Write lines

    print("Subnet part2 completed")


    for line6 in SubOut2:
        endlist.append(line6)

    print("Subnet part3 completed")

    for line7 in SubOut1:
        endlist.append(line7)

    print("Subnet part4 completed")

    lst8=[]

    for line10 in endlist:
        line10['CIDR']=ipaddress.ip_network(line10['CIDR'])
        line10['Mask']=line10['CIDR'].netmask
        print("{} is line10 try".format(line10))
        if str(line10['CIDR']) not in lst8:
            msklst.append(line10)
            lst8.append(str(line10['CIDR']))
            print("{} is line10 append".format(line10))



    srtlst=sorted(msklst, key=operator.itemgetter('Mask'), reverse=True)

    for lip in srtlst:
        alphlst.append(lip)






def all_true(items):
    return all(x == "True" for x in items)

lstadd=[]

def in_lst():

    global lst4
    global SubnetDic2
    global lstadd

    lstadd=[]

    for l in lst4:
        if l in lst7:
            lstadd.append("True")
        else:
            lstadd.append("False")

    print(lstadd)
    print(lst4)

def chk_lst():

    print("running chk_lst")

    in_lst()

    global lstadd

    if all_true(lstadd):
        return True
    else:
        return False


pass_start=time.strftime("%I:%M:%S %p", time.localtime())
cnt=1
cProfile.run('program()', 'prostats')
pass_end=time.strftime("%I:%M:%S %p", time.localtime())
p = pstats.Stats('prostats')
p.print_stats(0)
print("Pass {0}. Start: {1} End: {2}".format(cnt, pass_start, pass_end))


while chk_lst() is False:
    pass_start2=time.strftime("%I:%M:%S %p", time.localtime())
    cnt = cnt + 1
    cProfile.run('program()', 'prostats2')
    pass_end2=time.strftime("%I:%M:%S %p", time.localtime())
    p = pstats.Stats('prostats2')
    p.print_stats(0)
    print("Pass {0}. Start: {1} End: {2}".format(cnt, pass_start2, pass_end2))


print("All Subnets Done")    


with open(r'C:\ExampleBefore.csv', newline='') as fin7,\
     open(r'C:\TstExample-sort1.csv', 'w', newline='') as fout5:

        read7 = DictReader(fin7)

        writenum6 = DictWriter(fout5, fieldnames=read7.fieldnames, extrasaction='ignore') 
        writenum6.writeheader()

        global alphlst

        for lime in alphlst:
           writenum6.writerow(lime)

        print("Write Complete")