<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def checkpoint(self, stage, msg=""):
 """ Touch checkpoint file for given stage and provide timestamp message. :param pypiper.Stage stage: Stage for which to mark checkpoint :param str msg: Message to embed in timestamp. :return bool: Whether a checkpoint file was written. """

        # Canonical usage model for Pipeline checkpointing through
        # implementations of this class is by automatically creating a
        # checkpoint when a conceptual unit or group of operations of a
        # pipeline completes, so fix the 'finished' parameter to the manager's
        # timestamp method to be True.
        return self.manager.timestamp(
                message=msg, checkpoint=stage.checkpoint_name, finished=True)