diff --git a/tradingagents/dataflows/alpha_vantage_common.py b/tradingagents/dataflows/alpha_vantage_common.py
index 409ff29ea7..55138892c6 100644
--- a/tradingagents/dataflows/alpha_vantage_common.py
+++ b/tradingagents/dataflows/alpha_vantage_common.py
@@ -4,6 +4,7 @@
 import json
 from datetime import datetime
 from io import StringIO
+from typing import Union
 
 API_BASE_URL = "https://www.alphavantage.co/query"
 
@@ -39,7 +40,7 @@ class AlphaVantageRateLimitError(Exception):
     """Exception raised when Alpha Vantage API rate limit is exceeded."""
     pass
 
-def _make_api_request(function_name: str, params: dict) -> dict | str:
+def _make_api_request(function_name: str, params: dict) -> Union[dict, str]:
     """Helper function to make API requests and handle responses.
     
     Raises:
diff --git a/tradingagents/dataflows/alpha_vantage_news.py b/tradingagents/dataflows/alpha_vantage_news.py
index 8124fb45df..09eda713a8 100644
--- a/tradingagents/dataflows/alpha_vantage_news.py
+++ b/tradingagents/dataflows/alpha_vantage_news.py
@@ -1,6 +1,7 @@
 from .alpha_vantage_common import _make_api_request, format_datetime_for_api
+from typing import Union
 
-def get_news(ticker, start_date, end_date) -> dict[str, str] | str:
+def get_news(ticker, start_date, end_date) -> Union[dict[str, str], str]:
     """Returns live and historical market news & sentiment data from premier news outlets worldwide.
 
     Covers stocks, cryptocurrencies, forex, and topics like fiscal policy, mergers & acquisitions, IPOs.
@@ -24,7 +25,7 @@ def get_news(ticker, start_date, end_date) -> dict[str, str] | str:
     
     return _make_api_request("NEWS_SENTIMENT", params)
 
-def get_insider_transactions(symbol: str) -> dict[str, str] | str:
+def get_insider_transactions(symbol: str) -> Union[dict[str, str], str]:
     """Returns latest and historical insider transactions by key stakeholders.
 
     Covers transactions by founders, executives, board members, etc.