chmod之后的OSError django

Question

我有一个上传系统，今天早上工作正常，但是当我今天下午回来时，我收到了这个错误：

[Errno 13] Permission denied: '/media/media'

Request Method:     POST
Request URL:    http://localhost:8000/admin/blog/hojas/add/
Django Version:     1.6.1
Exception Type:     OSError
Exception Value:    

[Errno 13] Permission denied: '/media/media'

Exception Location:     /usr/lib/python2.7/os.py in makedirs, line 157
Python Executable:  /usr/bin/python
Python Version:     2.7.5
Python Path:    

['/home/yabir/Documentos/taqwim/proyecto',
 '/usr/lib/python2.7',
 '/usr/lib/python2.7/plat-x86_64-linux-gnu',
 '/usr/lib/python2.7/lib-tk',
 '/usr/lib/python2.7/lib-old',
 '/usr/lib/python2.7/lib-dynload',
 '/usr/local/lib/python2.7/dist-packages',
 '/usr/lib/python2.7/dist-packages',
 '/usr/lib/python2.7/dist-packages/PILcompat',
 '/usr/lib/python2.7/dist-packages/gtk-2.0',
 '/usr/lib/python2.7/dist-packages/ubuntu-sso-client',
 '/usr/lib/python2.7/dist-packages/ubuntuone-client',
 '/usr/lib/python2.7/dist-packages/ubuntuone-control-panel',
 '/usr/lib/python2.7/dist-packages/ubuntuone-storage-protocol',
 '/home/my_username/projects']

看到它后，我开始给我的文件夹755权限，但它仍然无效。