README.md in acb-0.1.5 vs README.md in acb-0.2.0

@@ -59,9 +59,26 @@
     [:user, :comments]
   end
 end
 
 PostCsvBuilder.new(user_id).to_csv
+
+# or
+
+class PostCsvBuilder
+  include Acb
+
+  add_column name: 'id'
+  add_column name: 'User Name', index: 'user.name'
+  add_column name: 'created_at', format: '%Y-%m-%d'
+  add_column name: 'Comment Amount', index: 'comments.size'
+  add_column name: 'First Comment', index: ->(post) { post.comments.first&.content }
+end
+
+builder = PostCsvBuilder.new
+relations = Post.where(user_id: user_id).preload(:user, :comments)
+builder.load_from(relations)
+builder.to_csv
 ```
 
 ## Code of Conduct
 
 Everyone interacting in the Acb project's codebases, issue trackers, chat rooms and mailing lists is expected to follow the [code of conduct](https://github.com/kakubin/acb/blob/main/CODE_OF_CONDUCT.md).