Maze_explorer

Hi everybody, I need help with this code, I don´t understand this message…
If you can help me, I appreciate a lot…

this is the code on graph.py
from vertex import Vertex

class Graph:

def init(self):

self.graph_dict = {}

def add_vertex(self, node):

self.graph_dict[node.value] = node

def add_edge(self, from_node, to_node, weight = 0):

self.graph_dict[from_node.value].add_edge(to_node.value, weight)

self.graph_dict[to_node.value].add_edge(from_node.value, weight)

def explore(self):

print("Exploring the graph....\n")

#FILL IN EXPLORE METHOD BELOW

def print_map(self):

print("\nMAZE LAYOUT\n")

for node_key in self.graph_dict:

  print("{0} connected to...".format(node_key))

  node = self.graph_dict[node_key]

  for adjacent_node, weight in node.edges.items():

    print("=> {0}: cost is {1}".format(adjacent_node, weight))

  print("")

print("")

def build_graph():

graph = Graph()

MAKE ROOMS INTO VERTICES BELOW…

entrance = Vertex(“entrance”)

ADD ROOMS TO GRAPH BELOW…

graph.add_vertex(entrance)

ante_chamber = Vertex(“ante-chamber”)

graph.add_vertex(ante_chamber)

kings_room = Vertex(“King’s room”)

graph.add_vertex(kings_room)

grand_gallery = Vertex(“grand gallery”)

treasure_room = Vertex(“treasure room”)

ADD EDGES BETWEEN ROOMS BELOW…

graph.add_edge(entrance, ante_chamber, 7)

graph.add_edge(entrance, kings_room, 3)

graph.add_edge(kings_room, ante_chamber, 1)

graph.add_edge(grand_gallery, ante_chamber, 2)

graph.add_edge(grand_gallery, kings_room, 2)

graph.add_edge(treasure_room, ante_chamber, 6)

graph.add_edge(treasure_room, grand_gallery, 4)

DON’T CHANGE THIS CODE

graph.print_map()

return graph

This is the message error:
Traceback (most recent call last):
excavation_site = build_graph()
File “/home/ccuser/workspace/maze-explorer/graph.py”, line 60 in build_graph
graph.add_edge(grand_gallery, ante_chamber, 2)
File “/home/ccuser/workspace/maze-explorer/graph.py”, line 11 , in add_edge
self.graph_dict[from_node.value].add_edge(to_node.value, weight)
keyError: ‘grand gallery’

A key error suggests that the ditionary you’re looking for this key in doesn’t actually contain that key. Check for typos and if that’s no good you’ll have to work back from that stack trace to find your bug.

Thank you very much :+1:

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