def remove_subsegment(self, subsegment):
        """
        Remove input subsegment from child subsegemnts and
        decrement parent segment total subsegments count.

        :param Subsegment: subsegment to remove.
        """
        super(Subsegment, self).remove_subsegment(subsegment)
        self.parent_segment.decrement_subsegments_size()
Remove input subsegment from child subsegemnts and
        decrement parent segment total subsegments count.

        :param Subsegment: subsegment to remove.