text: #!/usr/bin/env python
  
  import yaml
  import custom_class
  
  my_obj = custom_class.MyClass()
  my_obj.add_item(1)
  my_obj.add_item(2)
  my_obj.add_item(3)
  
  yaml_file = open('custom_class.yaml', 'w')
  yaml.dump(my_obj, yaml_file)
  yaml_file.close()
  