# File lib/fog/aws/requests/rds/create_db_parameter_group.rb, line 34
        def create_db_parameter_group(group_name, group_family, description)
          response = Excon::Response.new
          if self.data[:parameter_groups] and self.data[:parameter_groups][group_name]
            raise Fog::AWS::RDS::IdentifierTaken.new("Parameter group #{group_name} already exists")
          end
          
          data = {
            'DBParameterGroupName' => group_name,
            'DBParameterGroupFamily' => group_family.downcase,
            'Description' => description
          }
          self.data[:parameter_groups][group_name] = data
          
          response.body = {
            "ResponseMetadata"=>{ "RequestId"=> Fog::AWS::Mock.request_id },
            "CreateDBParameterGroupResult"=> {"DBParameterGroup"=> data}
          }
          response.status = 200
          response
          
        end