modify temp variable name

examples/SAGPool/layers.py

@@ -52,7 +52,7 @@ def topk_pool(gw, score, graph_id, ratio):
     max_num_nodes = L.cast(max_num_nodes, dtype="int32")
 
     index = L.arange(0, gw.num_nodes, dtype="int64")
-    temp = L.gather(graph_lod, graph_id, overwrite=False)
+    offset = L.gather(graph_lod, graph_id, overwrite=False)
     index = (index - temp) + (graph_id * max_num_nodes)
     index.stop_gradient = True