Please implement the A* search algorithm in Python for the problem scenario below. Please explain your code and your approach.    PROBLEM SCENARIO  On holiday, a flight currently wants to travel to Bucharest from Arad. But there is no direct way to Bucharest from Arad. However, the cities are connected with each other like a graph. The distance between the connected cities are given. The flight wants to travel through the most optimal way. To find the optimal path to travel, another information is provided: the straight line distance between any city and the final destination (Bucharest). Now apply A* search to determine the most optimal value for the route Arad to Bucharest and help the flight. You have to use the straight line distance as the heuristic value for the cities. City    Heuristic value    City            Heuristic value Arad     366                    Mehadia       241 Bucharest    0                   Neamt          234 Craiova     160                  Oradea        380 Eforie         161                 Pitesti          100 Fagaras      176                 Rimnicu Vilcea 193 Dobreta      242                Timisoara      329 Hirsova      151                 Urziceni         80 lasi             226                  Vaslui          199 Lugoj         244                 Zerind            374   For simplicity, assume these notations Arad  A  Neamt  F Bucharest Z  Oradea B Craiova S  Pitesti P Eforie T  Rimnicu Vilcea R Fagaras O  Timisoara C Dobreta V  Urziceni D Hirsova N  Vaslui H lasi Q  Zerind E Lugoj G Mehadia L INPUTS Your txt file should take each node followed by each destination it can reach and their corresponding distance and heuristics. You are to read the file then ask the user to input the starting and the destination point. OUTPUTS The output will contain the total distance from the starting point to the destination followed by printing the nodes it followed to calculate the distance. SAMPLE INPUT In the text file: Arad 366 Zerind 75 Sibiu 140 Timisoara 118 Zerind 374 Arad 75 Oradea 71 Oradea 380 Zerind 71 Sibiu 151 ... ... ... ... ... ... Bucharest 0 Pitesti 101 Fagaras 211 Giurgiu 90 Urziceni 85 Giurgiu 77 Bucharest 90 ... ... ... ... ... … The text file is arranged as follows: Each line starts with a node followed by the heuristic of that node Then the neighboring nodes and the distance from the parent node is given as a pair All neighboring city-distance pairs are listed after the heuristic. For example, the text file starts with Arad which has a heuristic of 366. It is the parent node to Zerind, Sibiu and Timisoara which are 75, 140 and 118 km away from Arad. Notice that since Bucharest is the End node which is why it has a heuristic of 0. In console: Start node: Arad Destination: Bucharest Sample output: Path: Arad -> Sibiu -> Rimnicu -> Pitesti -> Bucharest Total distance: 418 km If there is no path found from the Start node to the End node, simply print “NO PATH FOUND