diff --git a/Doc/tutorial/datastructures.rst b/Doc/tutorial/datastructures.rst
index ff4c797..5c6b65f 100644
--- a/Doc/tutorial/datastructures.rst
+++ b/Doc/tutorial/datastructures.rst
@@ -78,7 +78,7 @@
    Return the number of times *x* appears in the list.
 
 
-.. method:: list.sort(key=None, reverse=False)
+.. method:: list.sort(*, key=None, reverse=False)
    :noindex:
 
    Sort the items of the list in place (the arguments can be used for sort