Updated app.py to use ollama instead of gpt-4o

app.py

@@ -14,6 +14,7 @@ from langchain.embeddings import HuggingFaceEmbeddings
 from langchain_chroma import Chroma
 from langchain.memory import ConversationBufferMemory
 from langchain.chains import ConversationalRetrievalChain
+from langchain_ollama import ChatOllama
 import numpy as np
 from sklearn.manifold import TSNE
 import plotly.graph_objects as go
@@ -32,6 +33,7 @@ os.environ['OPENAI_API_KEY'] = os.getenv('OPENAI_API_KEY')
 
 folder = "my-knowledge-base/"
 db_name = "vectorstore_db"
+MODEL = "llama3.2:latest"
 
 def process_files(files):
     os.makedirs(folder, exist_ok=True)
@@ -73,7 +75,7 @@ def process_files(files):
     collection = vectorstore._collection
     result = collection.get(include=['embeddings', 'documents', 'metadatas'])
 
-    llm = ChatOpenAI(temperature=0.7, model_name=MODEL)
+    llm = ChatOllama(temperature=0.7, model=MODEL)
     memory = ConversationBufferMemory(memory_key='chat_history', return_messages=True)
     retriever = vectorstore.as_retriever(search_kwargs={"k": 35})
     global conversation_chain