[Bug]: <title>extract entities by nltk strategy found Error: "Column(s) ['description', 'source_id'] do not exist"

[HENScience]

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Describe the bug

When I set the strategy of entity extraction to nltk, the following error occurs during index creation:
KeyError: "Column(s) ['description', 'source_id'] do not exist"
graphrag\index\operations\extract_entities\extract_entities.py", line 171, in _merge_entities
.agg(description=("description", list), text_unit_ids=("source_id", list))

Steps to reproduce

No response

Expected Behavior

No response

GraphRAG Config Used

# Paste your config here
entity_extraction:
  prompt: "prompts/entity_extraction.txt"
  entity_types: [organization,person,geo,event]
  max_gleanings: 1
  strategy: 
    type: nltk

Logs and screenshots

No response

Additional Information

• GraphRAG Version: v1.1.1
• Operating System: window11 Professional
• Python Version: 3.10