code: def test_get_variable_default_value(self):
      with redirect_stdout(StringIO()) as stdout:
          variable_command.variables_get(
              self.parser.parse_args(
                  ["variables", "get", "baz", "--default", "bar"]
              )
          )
          assert "bar\n" == stdout.getvalue()
  
imports: from __future__ import annotations
  import os
  from contextlib import redirect_stdout
  from io import StringIO
  import pytest
  from sqlalchemy import select
  from airflow import models
  from airflow.cli import cli_parser
  from airflow.cli.commands import variable_command
  from airflow.models import Variable
  from airflow.utils.session import create_session
  from tests.test_utils.db import clear_db_variables
label_desc: Use image node_id 7 for calling the TestCliVariables obj's underlying member method code with example usage: obj.test_get_variable_default_value() without return types