Given a list of sentences, you should generate a general sentence (topic) that encompasses all sentences. If there are no general sentence that could explain the sentences, generate "None"
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- sentences:
* Generative Retrieval: A prior work that  first propose a generative retrieval model, which achieves comparable or higher performances on entity retrieval tasks compared to bi-encoder models.
* Generative Retrieval: A prior work that show generative retrieval methods in no-hop retrieval settings.
* Generative Retrieval: A prior work that further improves the performance of generative retrieval by psuedo-query generation.
- topic:
Various generative retrieval methods
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- sentences:
* Tactile Graphics: Prior works that explored the applications of tactile graphics in educational models.
* Design Space: A prior work that explored techniques enabling the transition from physical to AR content in educational contexts.
* Children's Graphical Understanding: A prior work that has provided pedagogical guidelines and instructional implications for assessing student visualization comprehension and partnering with education researchers.
- topic: Provide the entire answer in JSON format.
user