'Set the content of the node'

def set_node_info(self):

    for node in self.scene.nodes():
        node.set_rect(QRectF())
        self.update_node_info(node)
    w = max(([n.rect().width() for n in self.scene.nodes()] + [0]))
    if (w > self.max_node_width):
        w = self.max_node_width
    for node in self.scene.nodes():
        rect = node.rect()
        node.set_rect(QRectF(rect.x(), rect.y(), w, rect.height()))
    self.scene.fix_pos(self.root_node, 10, 10)
