在AGE Viewer中使用以下代码示例来显示路径：

from age.tools import visualization
vis = visualization.Visualization(filename='path_to_age_file.age')
graph = vis.graph()
path = [(1,2), (2,3), (3,4)]
# set path as red
color = 'red'
for i, (u, v) in enumerate(path[:-1]):
  graph.edge(u, v, color=color, penwidth=3)
  # set last node as rectangle
  if i == len(path) - 2:
    graph.node(v, shape='rectangle', width=0.5)
# view graph
graph.view()

注意：代码示例中的"path_to_age_file.age"应替换为AGE文件的实际路径，而“path”应替换为要显示的路径。这将在AGE Viewer中显示路径，并将路径中的最后一个节点设置为一个矩形。可以通过更改颜色和线宽等属性来自定义路径的外观。