Prepare v4.2.1.
diff --git a/README.rst b/README.rst
index 6126d49..9fd8c36 100644
--- a/README.rst
+++ b/README.rst
@@ -85,7 +85,7 @@
 License
 ------------------------------------------------------------------------
 
-Copyright (c) 2014-2020 Thomas Kemmer.
+Copyright (c) 2014-2021 Thomas Kemmer.
 
 Licensed under the `MIT License`_.