      "    * Yes\n",
      "* Can we assume we already have Graph and Node classes?\n",
      "    * Yes\n",
      "* Can we assume the inputs are valid?\n",
      "    * Yes\n",
      "* Can we assume this fits memory?\n",
      "    * Yes"
     ]
    },
 
</s>
    "* Can we assume this is a connected graph?\n",
    "    * Yes\n",
      "    * Yes\n",
      "* Can we assume we already have Graph and Node classes?\n",
      "    * Yes\n",
    "* Can we assume this is a connected graph?\n",
    "    * Yes\n",
      "* Can we assume the inputs are valid?\n",
      "    * Yes\n",
      "* Can we assume this fits memory?\n",
      "    * Yes"
     ]
    },
keep keep add keep keep keep keep keep keep
 Update graphs challenges to add connected constraint (#151)
graphs_trees/graph_path_exists/path_exists_solution.ipynb