# File lib/fog/aws/requests/rds/modify_db_parameter_group.rb, line 44
        def modify_db_parameter_group(group_name, parameters)
          group = self.data[:parameter_groups][group_name]

          unless group
            raise Fog::AWS::RDS::NotFound.new("Parameter group not found")
          end

          parameters.each do |p|
            p.merge!(
              "Source"        => "user",
              "IsModifiable"  => true,
              "Description"   => "some string",
              "DataType"      => "string",
              "AllowedValues" => p["ParameterValue"],
              "ApplyType"     => "dynamic"
            )
          end

          group[:parameters] = parameters

          self.data[:parameter_groups][group_name] = group

          response = Excon::Response.new
          response.body = {
            "ResponseMetadata"             => {"RequestId"            => Fog::AWS::Mock.request_id},
            "ModifyDBParameterGroupResult" => {"DBParameterGroupName" => group_name}
          }
          response.status = 200
          response
        end