Update app.py

app.py

@@ -12,7 +12,7 @@ from tools.final_answer import FinalAnswerTool as FinalAnswer
 model = LiteLLMModel(
 max_tokens=5000,
 model_id='anthropic/claude-3-5-haiku-20241022',
-api_key=os.environ['ANTHROPIC_API_KEY'],
+api_key=os.getenv('ANTHROPIC_API_KEY'),
 )
 
 final_answer = FinalAnswer()