code: def test_code_exec_with_skills(self, code_manager: CodeManager):
      code = """plot_salaries()
  result = {'type': 'number', 'value': 1 + 1}"""
  
      @skill
      def plot_salaries() -> str:
          """Plots salaries"""
          return "return {'type': 'number', 'value': 1 + 1}"
  
      sm = SkillsManager()
      sm.add_skills(plot_salaries)
      exec_context = CodeExecutionContext(uuid.uuid4(), sm)
      result = code_manager.execute_code(code, exec_context)
  
      assert len(exec_context._skills_manager.used_skills) == 1
      assert (
          exec_context._skills_manager.used_skills[0] == "plot_salaries"
      )
      assert result == {"type": "number", "value": 1 + 1}
  
imports: from typing import Optional
  from unittest.mock import MagicMock, Mock, patch
  import uuid
  import pandas
  import pytest
  from pandasai.agent import Agent
  from pandasai.helpers.code_manager import CodeExecutionContext, CodeManager
  from pandasai.helpers.skills_manager import SkillsManager
  from pandasai.llm.fake import FakeLLM
  from pandasai.skills import skill, Skill
  from pandasai.smart_dataframe import SmartDataframe
label_desc: Use image node_id 19 for calling the TestSkills obj's underlying member method code with example usage: obj.test_code_exec_with_skills(code_manager) and returns: str