'NoneType' object has no attribute 'get' when using neo4j as graph storage

[RuiC8]

First, I tried to use the default graph_storage (NetworkXStorage) to build graphrag, and it run successfully. After I switched to Neo4j graph storage, I received the following error when building the graphrag. Does anyone know how to resolve this issue?

AttributeError                            Traceback (most recent call last)
Cell In[17], line 2
      1 with open("[./example_data/rm.txt](https://vscode-remote+ssh-002dremote-002b10-002e0-002e30-002e50.vscode-resource.vscode-cdn.net./example_data/rm.txt)") as f:
----> 2     graph_func.insert(f.read())

File [~/notebooks/KG/GraphRAG/nano-graphrag/nano_graphrag/graphrag.py:207](https://vscode-remote+ssh-002dremote-002b10-002e0-002e30-002e50.vscode-resource.vscode-cdn.net/home/rchen/notebooks/KG/GraphRAG/test_src/GRAG_tools/~/notebooks/KG/GraphRAG/nano-graphrag/nano_graphrag/graphrag.py:207), in GraphRAG.insert(self, string_or_strings)
    205 def insert(self, string_or_strings):
    206     loop = always_get_an_event_loop()
--> 207     return loop.run_until_complete(self.ainsert(string_or_strings))

File [~/miniconda3/envs/graph_env/lib/python3.9/site-packages/nest_asyncio.py:98](https://vscode-remote+ssh-002dremote-002b10-002e0-002e30-002e50.vscode-resource.vscode-cdn.net/KG/GraphRAG/test_src/GRAG_tools/~/miniconda3/envs/graph_env/lib/python3.9/site-packages/nest_asyncio.py:98), in _patch_loop..run_until_complete(self, future)
     95 if not f.done():
     96     raise RuntimeError(
     97         'Event loop stopped before Future completed.')
---> 98 return f.result()

File [~/miniconda3/envs/graph_env/lib/python3.9/asyncio/futures.py:201](https://vscode-remote+ssh-002dremote-002b10-002e0-002e30-002e50.vscode-resource.vscode-cdn.net/KG/GraphRAG/test_src/GRAG_tools/~/miniconda3/envs/graph_env/lib/python3.9/asyncio/futures.py:201), in Future.result(self)
    199 self.__log_traceback = False
    200 if self._exception is not None:
--> 201     raise self._exception
    202 return self._result

File [~/miniconda3/envs/graph_env/lib/python3.9/asyncio/tasks.py:256](https://vscode-remote+ssh-002dremote-002b10-002e0-002e30-002e50.vscode-resource.vscode-cdn.net/KG/GraphRAG/test_src/GRAG_tools/~/miniconda3/envs/graph_env/lib/python3.9/asyncio/tasks.py:256), in Task.__step(***failed resolving arguments***)
    252 try:
...
    508 edges_may_truncate_list_data = truncate_list_by_token_size(
    509     edges_list_data, key=lambda x: x[3], max_token_size=max_token_size [/](https://vscode-remote+ssh-002dremote-002b10-002e0-002e30-002e50.vscode-resource.vscode-cdn.net/)[/](https://vscode-remote+ssh-002dremote-002b10-002e0-002e30-002e50.vscode-resource.vscode-cdn.net/) 2
    510 )

AttributeError: 'NoneType' object has no attribute 'get'

The graphrag with neo4j is initialized as follows:

graph_func = GraphRAG(
    graph_storage_cls=Neo4jStorage,
    addon_params=config,
    working_dir=WORKING_DIR,
    enable_llm_cache=True,
    best_model_max_async=5,
    cheap_model_max_async=5,
    embedding_func=local_embedding,
    entity_extraction_func=extract_entities_dspy
)