Update agent_langchain.py

agent_langchain.py

@@ -8,6 +8,7 @@ import numpy as np
 import chromadb
 from chromadb.utils import embedding_functions
 from chromadb.config import Settings
+from chromadb.api.models import Collection
 from langchain_google_genai import ChatGoogleGenerativeAI
 from langchain.agents import initialize_agent, Tool, AgentType
 from langchain.memory import ConversationBufferMemory