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Reverts LaunchAcademy/south_park_reviews#23


This would be better suited as an instance method on `User`.

```ruby
class User < ActiveRecord::Base
  def admin?
    role == 'admin'
  end
end
```

Then this can be used in your view when you have a user:

```html
<% if current_user && current_user.admin? %>
<% end %>
```