'Usage: downdir [remotedir] [localdir] - download a remote directory (recursively)
remotedir - remote directory at Baidu Yun (after app root directory), if not specified, it is set to the root directory at Baidu Yun
localdir - local directory. if not specified, it is set to the current directory'

def downdir(self, remotepath=None, localpath=None):

    rpath = get_pcs_path(remotepath)
    lpath = localpath
    if (not lpath):
        lpath = u''
    lpath = lpath.rstrip(u'/\\    ')
    return self.__downdir(rpath, lpath)
