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#---
# demonstrates use of method missing


resource :electricity, :power
resource :acid, :type, :grade

item :secure_air_vent

item(:acid_bath).
  uses(acid(:type => :hcl, :grade => 5)).
  uses(electricity(:power => 12))

item(:camera).
  uses(electricity(:power => 1))

item(:small_power_plant).
  provides(electricity(:power => 11)).
  depends_on(:secure_air_vent)