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Graph/graph/traversing.py

@@ -15,7 +15,7 @@ def _traversing(to_visit: Union[FIFO, LIFO], graph: Graph, node: Node) -> Iterat
     """
     to_visit.add(node)
     visited = set()
-    parent = {}
+    parent = {}  # to store for each node from which node it has been discovered
     path = []
     while to_visit:
         node = to_visit.pop()
@@ -29,7 +29,7 @@ def _traversing(to_visit: Union[FIFO, LIFO], graph: Graph, node: Node) -> Iterat
                 parent[edge.target] = edge
                 to_visit.add(edge.target)
         if node in parent:
-            path.append(parent[node])
+            path.append(parent[node])  # the starting node has no parent
         yield node, path