def _make_x_title(self):
        """Make the X-Axis title"""
        y = (self.height - self.margin_box.bottom + self._x_labels_height)
        if self._x_title:
            for i, title_line in enumerate(self._x_title, 1):
                text = self.svg.node(
                    self.nodes['title'],
                    'text',
                    class_='title',
                    x=self.margin_box.left + self.view.width / 2,
                    y=y + i * (self.style.title_font_size + self.spacing)
                )
                text.text = title_line
Make the X-Axis title