def add_subsegment(self, subsegment):
        """
        Add input subsegment as a child subsegment.
        """
        self._check_ended()
        subsegment.parent_id = self.id
        self.subsegments.append(subsegment)
def add_subsegment ( self , subsegment ) : self . _check_ended ( ) subsegment . parent_id = self . id self . subsegments . append ( subsegment )
Add input subsegment as a child subsegment.