Convert more things
diff --git a/OpenSSL/crypto/x509.c b/OpenSSL/crypto/x509.c
index 2f12437..915a3b7 100644
--- a/OpenSSL/crypto/x509.c
+++ b/OpenSSL/crypto/x509.c
@@ -776,8 +776,7 @@
 }
 
 PyTypeObject crypto_X509_Type = {
-    PyObject_HEAD_INIT(NULL)
-    0,
+    PyVarObject_HEAD_INIT(&PyType_Type, 0)
     "X509",
     sizeof(crypto_X509Obj),
     0,