Dijkstra

def dijkstra(graph_in, src, dest, visited=None, distances=None, predecessors=None) -> list:

    if not predecessors:
        predecessors = {}
    if not distances:
        distances = {}
    if not visited:
        visited = []
    global g_path
    if src not in graph_in:
        raise TypeError("No source in graph")
    if dest not in graph_in:
        raise TypeError("No target in graph")

    if src == dest:
        path = []
        pred = dest
        while pred is not None:
            path.append(pred)
            g_path.append(pred)
            pred = predecessors.get(pred, None)
        g_path = g_path[::-1]
        print("Shortest path: " + str(path[::-1]))
        return path
    else:
        if not visited:
            distances[src] = 0

        for neighbour in graph_in[src]:
            if neighbour not in visited:
                new_distance = distances[src] + graph_in[src][neighbour]
                if new_distance < distances.get(neighbour, float('inf')):
                    distances[neighbour] = new_distance
                    predecessors[neighbour] = src

        visited.append(src)

        unvisited = {}

        for k in graph_in:
            if k not in visited:
                unvisited[k] = distances.get(k, float('inf'))
        x = min(unvisited, key=unvisited.get)

        dijkstra(graph_in, x, dest, visited, distances, predecessors)