# File lib/dragonfly/active_model_extensions/attachment_class_methods.rb, line 85
        def run_callbacks(name, model, attachment)
          attachment.should_run_callbacks = false
          callbacks[name].each do |callback|
            case callback
            when Symbol then model.send(callback)
            when Proc then model.instance_exec(attachment, &callback)
            end
          end
          attachment.should_run_callbacks = true
        end