class_docstr: mindsdb instance with temporal database and config
code: def teardown_class(cls):
      # remove tmp db file
      cls.db.session.close()
      os.unlink(cls.db_file)
  
      # remove environ for next tests
      del os.environ["MINDSDB_DB_CON"]
  
      # remove import of mindsdb for next tests
      unload_module("mindsdb")
  
imports: import copy
  import datetime
  import json
  import os
  import sys
  import tempfile
  from unittest import mock
  from pathlib import Path
  import duckdb
  import numpy
  import pandas
  from mindsdb_sql.render.sqlalchemy_render import SqlalchemyRender
  from mindsdb_sql import parse_sql
label_desc: Use image node_id 2 for calling the BaseUnitTest obj's underlying member method code with example usage: obj.teardown_class(cls) without return types