查询一个文件里面的内容是否出现在另一个文件里

import os
import sys

class Diff:
def __init__(self):
pass

def run(self, url_file, template_file):
f_template = open(template_file, 'r')
f_tem = f_template.readlines()

f_url = open(url_file, 'r')
url_lines = f_url.readlines()
flag = False

for url_line in url_lines:
flag = False
if url_line is None or url_line == "":
continue
else:
ss = url_line.split(".")
if len(ss) < 2:
continue
for tem_line in f_tem:
if url_line.find(tem_line.strip(' \r\n\t')) >= 0:
flag = True
continue

if flag == False:
print "%s::not exist" % url_line
f_template.close()
f_url.close()

if __name__ == "__main__":
differ = Diff()

differ.run("topic_url", "one_out")