Simple Python Implementing Breadth First Search Algorithm., enlightenment from here https://pythoninwonderland.wordpress.com/2017/03/18/how-to-implement-breadth-first-search-in-python/

bfs.py

graph = {
         'A': ['B', 'C', 'E'],
         'B': ['A', 'D', 'E'],
         'C': ['A', 'F', 'G'],
         'D': ['B'],
         'E': ['A', 'B', 'D'],
         'F': ['C'],
         'G': ['C']
}

def bfs_connected_graph(graph, start, goal):
    # keeping track visited
    visited = []
    queue = [[start]]

    if start == goal:
        "completed"

    while queue:
        print ("queue %r" % queue)
        # pop the first from queue
        path = queue.pop(0)
        print ("path : %r" % path)
        node = path[-1]
        print ("node %r" % node)
        if node not in visited:
            visited.append(node)
            print ("visited node: %r" % visited)
            neighbours = graph[node]
            print ("neighbours {}".format(neighbours))

            for n in neighbours:
                new_path = list(path)
                new_path.append(n)
                queue.append(n)
                if n == goal:
                    return print("finished %r" % new_path)
            visited.append(node)
            
    return "does not exist"

if __name__ == '__main__':
    start = input('choose starting graph ?[A-G](capitalize) > ')
    goal = input('choose your goal ?[A-G](capitalize) > ')
    bfs_connected_graph(graph, start, goal)