You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: user_satisfiability_graph.rb
    path of file: ./repos/coursemology2/lib/autoload/course/conditional
    
    the code of the file until where you have to start completion: # frozen_string_literal: true
# Satisfiability graph to evaluate the satisfiability of the conditionals for a course user.
class Course::Conditional::UserSatisfiabilityGraph
  class EdgeSet < Hash
    def initialize
      super { |h, k| h[k] = Set.new }
    end

    def add(source, edge)
      self[source] << edge
  
    
  def evaluate(course_user)
    satisfied_conditions = Set.new

    # Walk through the graph to find all the satisfied conditionals
    @graph.each do |conditional|
      # Remove conditional if they are not available.
      unless conditional.satisfiable?
        conditional.precluded_for!(course_user)
        next
      end

      conditions = conditional.specific_conditions.select { |c| c.satisfied_by?(course_user) }
      satisfied_conditions.merge(Set.new(conditions))

      # A conditional is satisfied if all its specific conditions are satisfied
      satisfied = conditions.count == conditional.specific_conditions.count
      satisfied ? conditional.permitted_for!(course_user) : conditional.precluded_for!(course_user)
    end