# File lib/fog/aws/requests/rds/download_db_logfile_portion.rb, line 19
        def download_db_logfile_portion(identifier=nil, filename=nil, opts={})
          params = {}
          params['DBInstanceIdentifier'] = identifier if identifier
          params['LogFileName'] = filename if filename
          params['Marker'] = opts[:marker] if opts[:marker]
          params['MaxRecords'] = opts[:max_records] if opts[:max_records]
          params['NumberOfLines'] = opts[:number_of_lines] if opts[:number_of_lines]

          request({
            'Action'  => 'DownloadDBLogFilePortion',
            :parser   => Fog::Parsers::AWS::RDS::DownloadDBLogFilePortion.new
          }.merge(params))
        end