weird python update

app/main.py

@@ -18,7 +18,7 @@ from pydantic import BaseModel
 # Import LangChain components
 from langchain_openai import ChatOpenAI
 from langchain.prompts import PromptTemplate
-from langchain.chains import LLMChain
+from langchain import RunnableSequence
 
 # Import the base LLM class to build our custom wrapper
 from langchain.llms.base import LLM
@@ -305,9 +305,9 @@ async def get_suggestions(
             input_variables=["prompt"],
             template=prompt
         )
-        suggestion_chain = LLMChain(llm=llm, prompt=suggestion_prompt)
+        suggestion_chain: RunnableSequence = suggestion_prompt | llm
         # Run the chain without additional inputs, since prompt is fully baked
-        raw_text = await asyncio.to_thread(suggestion_chain.run, {})
+        raw_text = await asyncio.to_thread(suggestion_chain.invoke, {})
         # Strip out any leading numbers, bullets or whitespace
         suggestion_array = [
             re.sub(r'^\s*[\-\d\.\)\s]+', '', line).strip()
@@ -396,13 +396,13 @@ async def generate_business_plan(data: GenerateRequest):
             llm_selected.max_tokens = 6000  # Increase max tokens to ensure full completion
             logging.info(f"Increased max_tokens from {original_max_tokens} to {llm_selected.max_tokens}")
         
-        plan_chain = LLMChain(llm=llm_selected, prompt=plan_prompt)
+        plan_chain: RunnableSequence = plan_prompt | llm_selected
         
         logging.info(f"Generated prompt for business plan with model {data.model}")
         
         try:
             logging.info(f"Generating business plan with model: {data.model}")
-            full_plan = await asyncio.to_thread(plan_chain.run, {"q_and_a": q_and_a, "business_context": business_context})
+            full_plan = await asyncio.to_thread(plan_chain.invoke, {"q_and_a": q_and_a, "business_context": business_context})
             logging.info(f"Successfully generated business plan with model: {data.model}")
             
             # Check if plan seems truncated