      test = TestGraph()
      test.test_graph()
  
  
  if __name__ == '__main__':
      main() 
</s> remove     def add_edge(self, source, dest, weight=0):
        if source not in self.nodes:
            self.add_node(source)
        if dest not in self.nodes:
            self.add_node(dest)
        self.nodes[source].adjacent[self.nodes[dest]] = weight </s> add  </s> remove     "    def add_edge(self, source, dest, weight=0):\n",
    "        if source not in self.nodes:\n",
    "            self.add_node(source)\n",
    "        if dest not in self.nodes:\n",
    "            self.add_node(dest)\n",
    "        self.nodes[source].adjacent[self.nodes[dest]] = weight"
 </s> add     "    def add_edge(self, id_source, id_dest, weight=0):\n",
    "        if id_source not in self.nodes:\n",
    "            self.add_node(id_source)\n",
    "        if id_dest not in self.nodes:\n",
    "            self.add_node(id_dest)\n",
    "        self.nodes[id_source].add_neighbor(self.nodes[id_dest], weight)\n",
    "\n",
    "    def add_undirected_edge(self, source, dest, weight=0):\n",
    "        self.add_edge(source, dest, weight)\n",
    "        self.nodes[dest].add_neighbor(self.nodes[source], weight)"
    test.test_graph_undirected()
      test = TestGraph()
      test.test_graph()
    test.test_graph_undirected()
  
  
  if __name__ == '__main__':
      main() 
keep add keep keep keep keep
 Rework graph challenge and solution (#86) 
graphs_trees/graph/test_graph.py