new_contents: #-*- coding:utf-8 -*-
  import logging
  logging.basicConfig(level=logging.ERROR)
  
  
  class FileSystemAdataper(object):
  	def __init__(self,*args,**kw):
  		pass
  	def move(self,src,dest):
  		pass
  	def copy(self,src,dest):
  		pass
  	def delete(self,src):
  		pass
  	def mkdir(self,dir_name):
  		pass
  	def rmdir(self,dir_name):
  		pass
  
subject: add file system adapater abstract class for different backend