diff --git a/src/packaging/licenses/__init__.py b/src/packaging/licenses/__init__.py
index 782fc8be..70f6628e 100644
--- a/src/packaging/licenses/__init__.py
+++ b/src/packaging/licenses/__init__.py
@@ -85,7 +85,7 @@ def normalize_license_expression(raw_license_expression: str) -> str | None:
         message = f"invalid license expression: {raw_license_expression}"
         raise ValueError(message) from None
 
-    # Take a final pass to check for unknown licenses/exceptions
+    # Take a final pass to check for unknown licenses/exceptions.
     normalized_tokens = []
     for token in tokens:
         if token in {"or", "and", "with", "(", ")"}: