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 def aStarAlgo(start_node, stop_node):

open_set = set(start_node)

closed_set = set()

g={}

parents = {}

g[start_node] = 0

parents[start_node] = start_node while len(open_set) > 0:

n = None

for v in open_set:

if n == None or g[v] + heuristic(v) <g[n] + heuristic(n): n=v

if n stop_node or Graph_nodes[n] == None: pass

else:

for (m, weight) in get_neighbors(n): open_set.add(m)

if m not in open_set and m not in closed_set:

parents[m] = n

g[m] = g[n] + weight

else:

if g[m]g[n] + weight: g[m] = g[n] + weight

parents[m] = n

if m in closed_set:

closed_set.remove(m)

open_set.add(m)

if n == None:

print('Path does not exist!") return None

if n == stop_node:

path = []

while parents[n] != n:

path.append(n)

n = parents[n]

path.append(start_node)

path.reverse()

print('Path found: {}'.format(path))

return path

open_set.remove(n)

closed_set.add(n)

print('Path does not exist!")

return None

def get_neighbors(v):

if v in Graph_nodes:

return Graph_nodes[v]

else:

return None

def heuristic(n):

H_dist = {

'A': 11,

'B': 6,

'C': 5,

'D': 7,

'E': 3,

'F': 6,

'G': 5,

'H': 3,

'': 1,

'':0

}

return H_dist[n]

Graph_nodes = {

'A': [('B', 6), ('F', 3)],

'B': [('A', 6), ('C', 3), ('D', 2)],

'C': [('B', 3), ('D', 1), ('E', 5)],

'D': [('B', 2), ('C', 1), ('E', 8)],

'E': [('C', 5), ('D', 8), (I', 5), ('J', 5)],

'F': [('A', 3), ('G', 1), ('H', 7)],

'G': [('F', 1), ('I', 3)],

'H': [('F', 7), ('I', 2)],

'I': [('E', 5), ('G', 3), ('H', 2), ('J', 3)],

}

aStarAlgo('A', 'I')