class_docstr: Unit tests for Agent class
code: def test_clarification_questions_max_3(self, sample_df, config):
      agent = Agent(sample_df, config, memory_size=10)
      agent._lake.llm.call = Mock()
      clarification_response = (
          '["What is happiest index for you", '
          '"What is unit of measure for gdp", '
          '"How many countries are involved in the survey", '
          '"How do you want this data to be represented"]'
      )
      agent._lake.llm.call.return_value = clarification_response
  
      questions = agent.clarification_questions(
          "What is the happiest country?"
      )
  
      assert isinstance(questions, list)
      assert len(questions) == 3
  
imports: from typing import Optional
  from unittest.mock import Mock
  from pandasai.agent import Agent
  import pandas
  import pytest
  from pandasai.llm.fake import FakeLLM
  from pandasai.prompts.clarification_questions_prompt import ClarificationQuestionPrompt
  from pandasai.prompts.explain_prompt import ExplainPrompt
  from pandasai.smart_datalake import SmartDatalake
label_desc: Use image node_id 11 for calling the TestAgent obj's underlying member method code with example usage: obj.test_clarification_questions_max_3(sample_df, config) without return types