def bfs(graph,source,target):
    # Initialize "visited" nodes.

    # Initialize "frontier" ("to do list") with source.

    # while there are nodes in the frontier/todo list

        # if this node has been visited, we're done with this node.

        # add node to visited nodes

        # is this the node you are looking for?  If so, return it.

        # get the edges from this node
        # Add these nodes to the end of the frontier/todo list

    # return value indicating that target wasn't found