code: def test_execute_func_success(self, tracker: QueryExecTracker):
      tracker._steps = []
  
      # Create a mock function
      mock_return_value = Mock()
      mock_return_value.to_string = Mock()
      mock_return_value.to_string.return_value = "Mock Result"
  
      mock_func = Mock()
      mock_func.return_value = mock_return_value
      mock_func.__name__ = "_get_prompt"
  
      # Execute the mock function using execute_func
      result = tracker.execute_func(mock_func, tag="_get_prompt")
  
      # Check if the result is as expected
      assert result.to_string() == "Mock Result"
      # Check if the step was added correctly
      assert len(tracker._steps) == 1
      step = tracker._steps[0]
      assert step["type"] == "Generate Prompt"
      assert step["success"] is True
  
imports: import json
  import os
  import time
  from typing import Optional
  from unittest.mock import MagicMock, Mock, patch
  import pandas
  import pytest
  from pandasai.helpers.query_exec_tracker import QueryExecTracker
  from pandasai.llm.fake import FakeLLM
  from pandasai.smart_dataframe import SmartDataframe
  from unittest import TestCase
  from datetime import datetime, timedelta
label_desc: Use image node_id 14 for calling the TestQueryExecTracker obj's underlying member method code with example usage: obj.test_execute_func_success(tracker) without return types