diff --git a/nikola/utils.py b/nikola/utils.py
index 2e0d86f20..3d6b9edad 100644
--- a/nikola/utils.py
+++ b/nikola/utils.py
@@ -576,7 +576,7 @@ def __repr__(self):
                                                            sort_keys=True))
 
 
-def pkg_resources(package, resource):
+def pkg_resources(package: str, resource: str) -> str:
     """Return the resource based on the python version."""
     if sys.version_info.minor <= 8:
         with resources.path(package, resource) as path: