diff --git a/pkgs/development/interpreters/python/2.6/default.nix b/pkgs/development/interpreters/python/2.6/default.nix
index 1217403f3fde..940b667e86a8 100644
--- a/pkgs/development/interpreters/python/2.6/default.nix
+++ b/pkgs/development/interpreters/python/2.6/default.nix
@@ -73,6 +73,8 @@ let
 
     passthru = rec {
       inherit zlibSupport;
+      isPy2 = true;
+      isPy26 = true;
       libPrefix = "python${majorVersion}";
       executable = libPrefix;
       sitePackages = "lib/${libPrefix}/site-packages";
diff --git a/pkgs/development/interpreters/python/2.7/default.nix b/pkgs/development/interpreters/python/2.7/default.nix
index df38299cb1ce..c19430862c21 100644
--- a/pkgs/development/interpreters/python/2.7/default.nix
+++ b/pkgs/development/interpreters/python/2.7/default.nix
@@ -87,6 +87,8 @@ let
 
     passthru = rec {
       inherit zlibSupport;
+      isPy2 = true;
+      isPy27 = true;
       libPrefix = "python${majorVersion}";
       executable = libPrefix;
       sitePackages = "lib/${libPrefix}/site-packages";
diff --git a/pkgs/development/interpreters/python/3.2/default.nix b/pkgs/development/interpreters/python/3.2/default.nix
index 3451b218f745..489d0509c1a4 100644
--- a/pkgs/development/interpreters/python/3.2/default.nix
+++ b/pkgs/development/interpreters/python/3.2/default.nix
@@ -69,7 +69,9 @@ stdenv.mkDerivation {
     tkSupport = (tk != null) && (tcl != null) && (libX11 != null) && (xproto != null);
     libPrefix = "python${majorVersion}";
     executable = "python3.2m";
-    is_py3k = true;
+    isPy3 = true;
+    isPy32 = true;
+    is_py3k = true;  # deprecated
     sitePackages = "lib/${libPrefix}/site-packages";
   };
 
diff --git a/pkgs/development/interpreters/python/3.3/default.nix b/pkgs/development/interpreters/python/3.3/default.nix
index 20fc66367caf..fcc033803498 100644
--- a/pkgs/development/interpreters/python/3.3/default.nix
+++ b/pkgs/development/interpreters/python/3.3/default.nix
@@ -66,7 +66,9 @@ stdenv.mkDerivation {
     tkSupport = (tk != null) && (tcl != null) && (libX11 != null) && (xproto != null);
     libPrefix = "python${majorVersion}";
     executable = "python3.3m";
-    is_py3k = true;
+    isPy3 = true;
+    isPy33 = true;
+    is_py3k = true;  # deprecated
     sitePackages = "lib/${libPrefix}/site-packages";
   };
 
diff --git a/pkgs/development/interpreters/python/3.4/default.nix b/pkgs/development/interpreters/python/3.4/default.nix
index a468807dcbda..3477cedf4b74 100644
--- a/pkgs/development/interpreters/python/3.4/default.nix
+++ b/pkgs/development/interpreters/python/3.4/default.nix
@@ -67,7 +67,9 @@ stdenv.mkDerivation {
     tkSupport = (tk != null) && (tcl != null) && (libX11 != null) && (xproto != null);
     libPrefix = "python${majorVersion}";
     executable = "python3.4m";
-    is_py3k = true;
+    isPy3 = true;
+    isPy34 = true;
+    is_py3k = true;  # deprecated
     sitePackages = "lib/${libPrefix}/site-packages";
   };