python 去掉重复行

#!/usr/bin/env pythonimport sys;def usage():        print("%s <src_file> <dst_file>" %sys.argv[0]);if "__main__" == __name__:        if len(sys.argv) != 3:                usage();                sys.exit(1);        #read file        hFileSrc = open(sys.argv[1], 'r');        strText = hFileSrc.read();        hFileSrc.close();        #operate        strText = strText.replace('\r', '');        strText = strText.replace('\n\n', '\n');        #write file        hFileDst = open(sys.argv[2], "w");        hFileDst.write(strText);        hFileDst.close();        print("fix succ!");