fix imports

app.py

@@ -1,9 +1,9 @@
 import os,re
 import gradio as gr
 import nest_asyncio
-from langchain import PromptTemplate
-from llama_index.core import PromptTemplate, StorageContext, load_index_from_storage
-from llama_index.llms.openai import OpenAI
+from llama_index.core import StorageContext, load_index_from_storage
+
+from telcom_core import query_rag_qa, query_graph_rag_qa, plot_full_kg, evaluate_llm
 
 import networkx as nx
 from pyvis.network import Network