module RubbishCode
    class AbstractStudent
        private_class_method :new
        attr_accessor :lastname, :firstname, :patronymic, :id

        def get_info
            raise "method not implemented"
        end

        def fio_info
            raise "method not implemented"
        end

        def contacts_info
            raise "method not implemented"
        end

        def to_s
            get_info
        end

        def as_json

        end
    end
end