diff --git a/ORStools/proc/isochrones_layer_proc.py b/ORStools/proc/isochrones_layer_proc.py
index bbf451bb..8a235141 100644
--- a/ORStools/proc/isochrones_layer_proc.py
+++ b/ORStools/proc/isochrones_layer_proc.py
@@ -207,7 +207,9 @@ def processAlgorithm(
         return {self.OUT: self.dest_id}
 
     # noinspection PyUnusedLocal
-    def postProcessAlgorithm(self, context, feedback) -> Dict[str, str]:
+    def postProcessAlgorithm(
+        self, context: QgsProcessingContext, feedback: QgsProcessingFeedback
+    ) -> Dict[str, str]:
         """Style polygon layer in post-processing step."""
         # processed_layer = self.isochrones.calculate_difference(self.dest_id, context)
         processed_layer = QgsProcessingUtils.mapLayerFromString(self.dest_id, context)