code: def get_result_type(self):
      return DataTypes.ROW(
          [
              DataTypes.FIELD("a", DataTypes.BIGINT()),
              DataTypes.FIELD("b", DataTypes.BIGINT()),
          ]
      )
  
imports: import unittest
  from pandas.testing import assert_frame_equal
  from pyflink.common import Row
  from pyflink.table import expressions, ListView
  from pyflink.table.types import DataTypes
  from pyflink.table.udf import udf, udtf, udaf, AggregateFunction, TableAggregateFunction, udtaf
  from pyflink.testing import source_sink_utils
  from pyflink.testing.test_case_utils import PyFlinkBatchTableTestCase, PyFlinkStreamTableTestCase
label_desc: Use image node_id 7 for calling the CountAndSumAggregateFunction obj's underlying member method code with example usage: obj.get_result_type() and returns: DataTypes