The code : default_scope :order => ‘title’and this following error occurs :

Support for calling #default_scope without a block is removed. For example instead of `default_scope where(color: ‘red’)`, please use `default_scope { where(color: ‘red’) }`. (Alternatively you can just redefine self.default_scope.)

In order to fix this error, change your code to the following : 

default_scope  { order(‘title’) }