python调用rarfile报错RarCannotExec("Unrar not installed?

rar

由于rar通常为window下使用，须要额外的Python包rarfile。

可用地址： http://sourceforge.net/projects/rarfile.berlios/files/rarfile-2.4.tar.gz/download

解压到Python安装文件夹的/Scripts/文件夹下，在当前窗体打开命令行,

输入Python setup.py install

安装完毕。

import rarfile
import os
def un_rar(file_name):
    """unrar zip file"""
    rar = rarfile.RarFile(file_name)
    if os.path.isdir(file_name + "_files"):
        pass
    else:
        os.mkdir(file_name + "_files")
    os.chdir(file_name + "_files"):
    rar.extractall()
    rar.close()

错误打印：

Traceback (most recent call last):
File "D:/GTRWork/CI_PreSmoking/programautoupgrade/autoupgrade.py", line 180, in <module>
un_rar(PWD, "LMTFile.rar")
File "D:/GTRWork/CI_PreSmoking/programautoupgrade/autoupgrade.py", line 172, in un_rar
rar.extractall()
File "D:\Python27\lib\site-packages\rarfile.py", line 841, in extractall
self._extract(fnlist, path, pwd)
File "D:\Python27\lib\site-packages\rarfile.py", line 908, in _extract
p = custom_popen(cmd)
File "D:\Python27\lib\site-packages\rarfile.py", line 2902, in custom_popen
raise RarCannotExec("Unrar not installed? (rarfile.UNRAR_TOOL=%r)" % UNRAR_TOOL)
rarfile.RarCannotExec: Unrar not installed? (rarfile.UNRAR_TOOL='unrar')