# File lib/mongo_mapper/plugins/keys.rb, line 362
      def read_key(key_name)
        key_name_sym = key_name.to_sym
        if @_dynamic_attributes && @_dynamic_attributes.key?(key_name_sym)
          @_dynamic_attributes[key_name_sym]
        elsif key = keys[key_name.to_s]
          if key.ivar && instance_variable_defined?(key.ivar)
            value = instance_variable_get(key.ivar)
          else
            if key.ivar
              instance_variable_set key.ivar, key.get(nil)
            else
              @_dynamic_attributes[key_name_sym] = key.get(nil)
            end
          end
        end
      end