测试修改hosts文件py小工具

import sys,os
parm_list=sys.argv
HOST_PATH=r'C:\liuliang\flask_test\test\hosts'
class HostFile(object):
    def __init__(self,parm_list):
        self.parm_list=parm_list
        self.open_file()
        if len(parm_list)==1:
            self.get()
        else:
            method=parm_list[1]
            if hasattr(self,method):
                func=getattr(self,method)
                func()
            else:
                print('输入格式有误')
        self.close_file()

    def open_file(self):
        self.f=open(HOST_PATH,'r+',encoding='utf-8')
    def close_file(self):
        self.f.close()

    def get(self):
       for line in self.f:
           print(line.strip())
    def delete(self):
        ip=self.parm_list[2]
        new_f=open(r'C:\liuliang\flask_test\test\new_hosts','w',encoding='utf-8')
        for line in self.f:
            if ip in line:
                continue
            new_f.write(line)
        new_f.close()
        self.close_file()
        os.remove(HOST_PATH)
        os.rename(r'C:\liuliang\flask_test\test\new_hosts',r'C:\liuliang\flask_test\test\hosts')

    def update(self):
        ip = self.parm_list[2]
        domain=self.parm_list[3]

        new_f = open(r'C:\liuliang\flask_test\test\new_hosts', 'w', encoding='utf-8')
        for line in self.f:
            if ip in line or domain in line:

                new_f.write('\n#   %s         %s\n' % (ip, domain))
                continue

            new_f.write(line)
        new_f.close()
        self.close_file()
        os.remove(HOST_PATH)
        os.rename(r'C:\liuliang\flask_test\test\new_hosts',r'C:\liuliang\flask_test\test\hosts')

    def add(self):
        ip=self.parm_list[2]
        domain=self.parm_list[3]

        self.f.seek(0,2)

        self.f.write('\n#   %s         %s'%(ip,domain))

hostfile=HostFile(parm_list)