reranker fixed

backend/reranker.py

@@ -6,5 +6,5 @@ reranker = FlagReranker('BAAI/bge-reranker-large',
 
 def rerank(query: str, documents: [str], k: int) -> [str]:
     scores = reranker.compute_score([(query, document) for document in documents])
-    sorted_docs = sorted(enumerate(scores), key=lambda x: x[1], reverse=True)
-    return [sorted_docs[i] for i, _ in sorted_docs[:k]]
+    sorted_docs = sorted(zip(scores, documents), key=lambda x: x[0], reverse=True)
+    return sorted_docs[:k][1]