diff --git a/pkgs/development/python-modules/ipydatawidgets/default.nix b/pkgs/development/python-modules/ipydatawidgets/default.nix
index a0efa9b575d..e6e1e605cca 100644
--- a/pkgs/development/python-modules/ipydatawidgets/default.nix
+++ b/pkgs/development/python-modules/ipydatawidgets/default.nix
@@ -13,13 +13,13 @@
 
 buildPythonPackage rec {
   pname = "ipydatawidgets";
-  version = "4.2.0";
+  version = "4.1.0";
 
   disabled = isPy27;
 
   src = fetchPypi {
     inherit pname version;
-    sha256 = "d0e4b58b59b508165e8562b8f5d1dbfcd739855847ec0477bd9185a5e9b7c5bc";
+    sha256 = "d9f94828c11e3b40350fb14a02e027f42670a7c372bcb30db18d552dcfab7c01";
   };
 
   propagatedBuildInputs = [