[Issue]: <title> how to add a new "data key"?

[VanJess-820]

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Describe the issue

I want to add new data keys to each node in my output GraphML file. How should I modify the code。 Here is a part of my results：

#<node id="RHEUMATIC HEART DISEASE">
      <data key="d0">DISEASE</data>
      <data key="d1">Rheumatic heart disease (RHD) is a condition resulting from rheumatic fever that affects the heart valves and can lead to serious complications such as heart failure and stroke.</data>
      <data key="d2">87c683fa8578f7787a11a734f9186592</data>
    </node>
    <node id="HEART FAILURE">
      <data key="d0">DISEASE</data>
      <data key="d1">Heart failure (HF) is a chronic condition where the heart does not pump blood as well as it should, leading to symptoms like fatigue and shortness of breath.</data>
      <data key="d2">87c683fa8578f7787a11a734f9186592</data>
    </node>

Steps to reproduce

No response

GraphRAG Config Used

# Paste your config here

Logs and screenshots

No response

Additional Information

• GraphRAG Version:
• Operating System:
• Python Version:
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