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week3/material/agent_programs.py

@@ -80,6 +80,8 @@ def search_behaviour(percepts, actuators, search_function):
     # the search_function should return a goal_node (an instance of the class GraphNode)
     # given the present agent location and a goal function:
     # goal_node = search_function(agent_location, a_goal_function_for_charging_dock)
+    # If you have not implemented any goal function yet, for now you can use a lambda function
+    # always returning False: lambda node_state: False
     # if the goal_node was found (not None/False), then we can generate the path to the goal
     # with the method .get_path()
     # We can set the value of path_to_dock to the found path