You have indented part of your code in settings.py:
# Uncomment the next line to enable the admin:
'django.contrib.admin',
# Uncomment the next line to enable admin documentation:
#'django.contrib.admindocs',
'tinymce',
'sorl.thumbnail',
'south',
'django_facebook',
'djcelery',
'devserver',
'main',
Therefore, it is giving you an error.