add os var of iteration

app.py

@@ -129,7 +129,7 @@ agent = initialize_agent(tools, llm,
                          agent=AgentType.ZERO_SHOT_REACT_DESCRIPTION,
                          verbose = True,
                          handle_parsing_errors = True,
-                         max_iterations = 3,
+                         max_iterations = int(os.getenv("max_iterations")) ,
                          agent_kwargs={
                             'prefix': PREFIX,
                             'format_instructions': FORMAT_INSTRUCTIONS,