code: def test_presto_expand_data_array(self):
      cols = [
          {
              "column_name": "event_id",
              "name": "event_id",
              "type": "VARCHAR",
              "is_dttm": False,
          },
          {
              "column_name": "timestamp",
              "name": "timestamp",
              "type": "BIGINT",
              "is_dttm": False,
          },
          {
              "column_name": "user",
              "name": "user",
              "type": "ROW(ID BIGINT, FIRST_NAME VARCHAR, LAST_NAME VARCHAR)",
              "is_dttm": False,
          },
      ]
      data = [
          {
              "event_id": "abcdef01-2345-6789-abcd-ef0123456789",
              "timestamp": "1595895506219",
              "user": '[1, "JOHN", "DOE"]',
          }
      ]
      (
          actual_cols,
          actual_data,
          actual_expanded_cols,
      ) = PrestoEngineSpec.expand_data(cols, data)
      expected_cols = [
          {
              "column_name": "event_id",
              "name": "event_id",
              "type": "VARCHAR",
              "is_dttm": False,
          },
          {
              "column_name": "timestamp",
              "name": "timestamp",
              "type": "BIGINT",
              "is_dttm": False,
          },
          {
              "column_name": "user",
              "name": "user",
              "type": "ROW(ID BIGINT, FIRST_NAME VARCHAR, LAST_NAME VARCHAR)",
              "is_dttm": False,
          },
          {
              "column_name": "user.id",
              "name": "user.id",
              "type": "BIGINT",
              "is_dttm": False,
          },
          {
              "column_name": "user.first_name",
              "name": "user.first_name",
              "type": "VARCHAR",
              "is_dttm": False,
          },
          {
              "column_name": "user.last_name",
              "name": "user.last_name",
              "type": "VARCHAR",
              "is_dttm": False,
          },
      ]
      expected_data = [
          {
              "event_id": "abcdef01-2345-6789-abcd-ef0123456789",
              "timestamp": "1595895506219",
              "user": [1, "JOHN", "DOE"],
              "user.id": 1,
              "user.first_name": "JOHN",
              "user.last_name": "DOE",
          }
      ]
      expected_expanded_cols = [
          {
              "column_name": "user.id",
              "name": "user.id",
              "type": "BIGINT",
              "is_dttm": False,
          },
          {
              "column_name": "user.first_name",
              "name": "user.first_name",
              "type": "VARCHAR",
              "is_dttm": False,
          },
          {
              "column_name": "user.last_name",
              "name": "user.last_name",
              "type": "VARCHAR",
              "is_dttm": False,
          },
      ]
  
      self.assertEqual(actual_cols, expected_cols)
      self.assertEqual(actual_data, expected_data)
      self.assertEqual(actual_expanded_cols, expected_expanded_cols)
  
imports: from collections import namedtuple
  from textwrap import dedent
  from unittest import mock, skipUnless
  import pandas
  from flask.ctx import AppContext
  from sqlalchemy import types
  from sqlalchemy.sql import select
  from superset.db_engine_specs.presto import PrestoEngineSpec
  from superset.errors import ErrorLevel, SupersetError, SupersetErrorType
  from superset.sql_parse import ParsedQuery
  from superset.utils.database import get_example_database
  from tests.integration_tests.db_engine_specs.base_tests import TestDbEngineSpec
label_desc: Use image node_id 20 for calling the TestPrestoDbEngineSpec obj's underlying member method code with example usage: obj.test_presto_expand_data_array() without return types