code: def test_single_statement(self):
      main_db = get_example_database()
  
      if main_db.backend == "mysql":
          df = main_db.get_df("SELECT 1", None)
          self.assertEqual(df.iat[0, 0], 1)
  
          df = main_db.get_df("SELECT 1;", None)
          self.assertEqual(df.iat[0, 0], 1)
  
imports: import json
  from superset.utils.core import DatasourceType
  import textwrap
  import unittest
  from unittest import mock
  from superset import security_manager
  from superset.connectors.sqla.models import SqlaTable
  from superset.exceptions import SupersetException
  from superset.utils.core import override_user
  from tests.integration_tests.fixtures.birth_names_dashboard import load_birth_names_dashboard_with_slices, load_birth_names_data
  import pytest
  from sqlalchemy.engine.url import make_url
  from sqlalchemy.types import DateTime
  import tests.integration_tests.test_app
  from superset import app, db
  from superset.db_engine_specs.postgres import PostgresEngineSpec
  from superset.common.db_query_status import QueryStatus
  from superset.models.core import Database
  from superset.models.slice import Slice
  from superset.utils.database import get_example_database
  from .base_tests import SupersetTestCase
  from .fixtures.energy_dashboard import load_energy_table_with_slice, load_energy_table_data
label_desc: Use image node_id 12 for calling the TestDatabaseModel obj's underlying member method code with example usage: obj.test_single_statement() without return types