Refactor app.py to use Cohere API and update dependencies in requirements.txt

app.py

@@ -9,8 +9,8 @@ from langchain_core.messages import AIMessage, BaseMessage, HumanMessage
 from langchain_core.prompts import ChatPromptTemplate, MessagesPlaceholder
 from langchain_core.vectorstores import InMemoryVectorStore
 
-from langchain_groq import ChatGroq
-from langchain_huggingface import HuggingFaceEmbeddings
+from langchain_cohere import ChatCohere
+from langchain_cohere import CohereEmbeddings
 
 from langchain_text_splitters import RecursiveCharacterTextSplitter
 from langgraph.checkpoint.memory import MemorySaver
@@ -18,28 +18,22 @@ from langgraph.graph import START, StateGraph
 from langgraph.graph.message import add_messages
 from typing_extensions import Annotated, TypedDict
 
+
 import os
-GROQ_API_KEY = os.getenv("GROQ_API_KEY")
+COHERE_API_KEY = os.getenv("COHERE_API_KEY")
 
-llm = ChatGroq(model="llama-3.2-11b-text-preview", api_key=GROQ_API_KEY, temperature=0)
+llm = ChatCohere(model="c4ai-aya-expanse-32b", cohere_api_key=COHERE_API_KEY, temperature=0)
 
 loader = TextLoader("stj.txt")
 loader.load()
 docs = loader.load()
 
-model_name = "sentence-transformers/all-MiniLM-L6-v2"
-model_kwargs = {'device': 'cpu'}
-encode_kwargs = {'normalize_embeddings': False}
-hf = HuggingFaceEmbeddings(
-    model_name=model_name,
-    model_kwargs=model_kwargs,
-    encode_kwargs=encode_kwargs
-)
+embeddings = CohereEmbeddings(model="embed-multilingual-v3.0",cohere_api_key=COHERE_API_KEY)
 
 text_splitter = RecursiveCharacterTextSplitter(chunk_size=1000, chunk_overlap=200)
 splits = text_splitter.split_documents(docs)
 vectorstore = InMemoryVectorStore.from_documents(
-    documents=splits, embedding=hf
+    documents=splits, embedding=embeddings
 )
 retriever = vectorstore.as_retriever()
 

requirements.txt

@@ -1,6 +1,8 @@
-langchain==0.3.4
-langchain-community==0.3.3
-sentence-transformers==3.2.0
-langchain-huggingface==0.1.0
-langgraph==0.2.39
-langchain-groq==0.2.0
+gradio==5.5.0
+langchain==0.3.7
+langchain_cohere==0.3.1
+langchain_community==0.3.5
+langchain_core==0.3.15
+langchain_text_splitters==0.3.2
+langgraph==0.2.45
+typing_extensions==4.12.2