内网ip字典生成 python实现

f = open ('ip.txt','w')
for i in range(256):
    for j in range(256):
            for k in range (254):  #1-254
                ip_address = '10.'+str(i)+'.'+str(j)+'.'+str(k+1)+'\n'
                f.write(ip_address)
for i in range(16):
    for j in range(256):
            for k in range(254):   #1-254
                ip_address = '172.'+str(i+16)+'.'+str(j)+'.'+str(k+1)+'\n'
                f.write(ip_address)

for j in range(256):
        for k in range(254):   #1-254
            ip_address = '192.168.'+str(j)+'.'+str(k+1)+'\n'        
f.close()