    # File lib/fog/bin/virtual_box.rb, line 26
        def available?
          availability = if Gem::Specification.respond_to?(:find_all_by_name)
            !Gem::Specification.find_all_by_name('virtualbox').empty? # newest rubygems
          else
            !Gem.source_index.find_name('virtualbox').empty? # legacy
          end
          if availability
            for service in services
              for collection in self.class_for(service).collections
                unless self.respond_to?(collection)
                  self.class_eval "def self.\#{collection}\nself[:\#{service}].\#{collection}\nend\n", __FILE__, __LINE__
                end
              end
            end
          end
          availability
        end