text: """
  字典的常用操作
  
  Version: 0.1
  Author: 骆昊
  Date: 2018-03-06
  """
  
  
  def main():
      stu = {'name': '骆昊', 'age': 38, 'gender': True}
      print(stu)
      print(stu.keys())
      print(stu.values())
      print(stu.items())
      for elem in stu.items():
          print(elem)
          print(elem[0], elem[1])
      if 'age' in stu:
          stu['age'] = 20
      print(stu)
      stu.setdefault('score', 60)
      print(stu)
      stu.setdefault('score', 100)
      print(stu)
      stu['score'] = 100
      print(stu)
  
  
  if __name__ == '__main__':
      main()
  