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GitHub User: mgoggin
Looks like you're missing Ryan's set_default method. This is a custom method that Ryan created to avoid using Capistrano's built-in _cset method. It's located in base.rb.
If you've got base.rb in your recipes folder and it contains set_default, make sure you're loading it before all other recipes.
Edit: You can see what base.rb looks like in the show notes for episode 337 (Capistrano Recipes)
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