human
I am working on the file "Python/11_Progress.ipynb".
The first task is:
Deriving from the Command class
The traditional way of using Commands in ITK involves deriving from the Command class and adding to the ProcessObject.
Can you write Python program for it?
assistant
#Here is the Python program you requested.

class MyCommand(sitk.Command):
    def __init__(self, msg):
        # required
        super(MyCommand, self).__init__()
        self.msg = msg

    def __del__(self):
        print(f'MyCommand begin deleted: "{self.msg}"')

    def Execute(self):
        print(self.msg)

cmd1 = MyCommand("Start")
cmd2 = MyCommand("End")
filter.RemoveAllCommands()  # this line is here so we can easily re-execute this code block
filter.AddCommand(sitk.sitkStartEvent, cmd1)
filter.AddCommand(sitk.sitkEndEvent, cmd2)
filter.Execute()