python比较两个文件的差异

#version 0import sysf1 = open(sys.argv[1], "r")f2 = open(sys.argv[2], "r")fileOne = f1.readlines()fileTwo = f2.readlines()f1.close()f2.close()outFile1 = open(sys.argv[3], "w")outFile2 = open(sys.argv[4], "w")for i in fileOne:        if not i in fileTwo:                outFile1.write(i)for i in fileTwo:        if not i in fileOne:                outFile2.write(i)outFile1.close()outFile2.close()#first time refacotring import sysfrom operator import attrgetter,itemgetter#verify inputsUSAGE='''%s file1 file2 output1 output2'''% __file__if len(sys.argv)<5:        print USAGE        sys.exit(2)#open files with trytry:        f1 = open(sys.argv[1], "r")        f2 = open(sys.argv[2], "r")except Exception,e:        print 'encounter issues %s, while opening in files: %s %s' % (str(e),itemgetter(1)(sys.argv),itemgetter(2)(sys.argv))        sys.exit(1)fileOne = f1.readlines()fileTwo = f2.readlines()f1.close()f2.close()#open files with trytry:        outFile1 = open(sys.argv[3], "w")        outFile2 = open(sys.argv[4], "w")except Exception,e:        print 'encounter issues %s, while opening out files: %s %s' % (str(e),itemgetter(3)(sys.argv),itemgetter(4)(sys.argv))        sys.exit(1)l_minus=lambda x,y:list(set(x)-set(y))outFile1.write('\n'.join(l_minus(fileOne,fileTwo)))outFile2.write('\n'.join(l_minus(fileTwo,fileOne)))outFile1.close()outFile2.close()#2nd time refactoringimport sysfrom operator import attrgetter,itemgetter#verify inputsUSAGE='''%s file1 file2 output1 output2'''% __file__if len(sys.argv)<5:        print USAGE        sys.exit(2)#open files with trywith open(itemgetter(1)(sys.argv), "r") as f1, open(itemgetter(2)(sys.argv), "r") as f2:        fileOne = f1.readlines()        fileTwo = f2.readlines()#list subsetl_minus=lambda x,y:list(set(x)-set(y))#open files with trywith open(itemgetter(3)(sys.argv), "w") as outFile1, open(itemgetter(4)(sys.argv), "w") as outFile2:        outFile1.write('\n'.join(l_minus(fileOne,fileTwo)))        outFile2.write('\n'.join(l_minus(fileTwo,fileOne)))