code: def change_default_db(self, new_db):
      self.command_executor.change_default_db(new_db)
  
imports: from typing import Union
  from mindsdb_sql import parse_sql
  from mindsdb_sql.planner import utils
  from numpy import dtype
  from pandas.api import types
  from mindsdb.api.executor import SQLQuery, Column
  from mindsdb.api.mysql.mysql_proxy.utilities.lightwood_dtype import dtype
  from mindsdb.api.executor.command_executor import ExecuteCommands
  from mindsdb.api.mysql.mysql_proxy.utilities import SqlApiException
  from mindsdb.api.postgres.postgres_proxy.postgres_packets.postgres_fields import POSTGRES_TYPES
  from mindsdb.utilities import log
label_desc: Use image node_id 9 for calling the Executor obj's underlying member method code with example usage: obj.change_default_db(new_db) without return types