Update ai_engine.py

ai_engine.py

@@ -12,14 +12,13 @@ from transformers import (
     StoppingCriteriaList
 )
 from huggingface_hub import login, hf_hub_download
+from sentence_transformers import SentenceTransformer
 
 
 API_KEY = os.getenv("OPENROUTER_API_KEY")
 MODEL = os.getenv("OPENROUTER_MODEL", "google/gemma-2-9b-it:free")
-global _embed_model
-if _embed_model is None:
-    from sentence_transformers import SentenceTransformer
-    _embed_model = SentenceTransformer('all-MiniLM-L6-v2')
+
+_embed_model = SentenceTransformer('all-MiniLM-L6-v2')
 
 class LocalModelHandler:
     def __init__(self, repo_id, device=None, use_quantization=False):