多个文本文件两两碰撞相同内容

# -*- coding: cp936 -*-import os,sys,glob,itertoolsos.chdir(sys.path[0])def getsame(a,b):    la=[]    lb=[]    for i in open(a):        la.append(i.strip())    for i in open(b):        lb.append(i.strip())            ret =  list(set(la).intersection(set(lb)))      if len(ret)==0:        return a[:-4]+'-'+b[:-4]+' : 匹配个数 0'    else:        return a[:-4]+'-'+b[:-4]+'  : 匹配个数 '+str(len(ret))+'\r\n'+' '.join(ret)+'\r\n'fn=[]for i in glob.glob('*.txt'):    fn.append(i)for a,b in itertools.combinations(fn,2):    print getsame(a,b)