code: def find_shortest_path(graph, start, end, path=[]):
      """
      find the shortest path between two nodes
      """
      path = path + [start]
      if start == end:
          return path
      if start not in graph:
          return None
      shortest = None
      for node in graph[start]:
          if node not in path:
              newpath = find_shortest_path(graph, node, end, path)
              if newpath:
                  if not shortest or len(newpath) < len(shortest):
                      shortest = newpath
      return shortest
  
label_desc: Use image node_id 3 for calling a global function with example usage: find_shortest_path(graph, start, end, path) and returns: shortest, path, None