Fix pep8

src/View/MainWindow.py

@@ -919,7 +919,8 @@ class ApplicationWindow(QMainWindow, ListedSubWindow, WindowToolKit):
     ##################
 
     def ensure_current_reach(self):
-        """Offer a reach selection when needed; return False on cancellation."""
+        """Offer a reach selection when needed;
+        return False on cancellation."""
         if self._study is None:
             return False
         river = self._study.river