diff --git a/workflow/rocoto/tasks.py b/workflow/rocoto/tasks.py
index 8a40e645d0..d16a009eff 100644
--- a/workflow/rocoto/tasks.py
+++ b/workflow/rocoto/tasks.py
@@ -4,6 +4,7 @@
 from applications.applications import AppConfig
 import rocoto.rocoto as rocoto
 from wxflow import Template, TemplateConstants, to_timedelta
+from typing import List
 
 __all__ = ['Tasks']
 
@@ -124,7 +125,7 @@ def _template_to_rocoto_cycstring(self, template: str, subs_dict: dict = {}) ->
                                              rocoto_conversion_dict.get)
 
     @staticmethod
-    def _get_forecast_hours(cdump, config) -> list[str]:
+    def _get_forecast_hours(cdump, config) -> List[str]:
         fhmin = config['FHMIN']
         fhmax = config['FHMAX']
         fhout = config['FHOUT']