diff --git a/OpenSSL/test/test_ssl.py b/OpenSSL/test/test_ssl.py
index beb5d28..fdeff9d 100644
--- a/OpenSSL/test/test_ssl.py
+++ b/OpenSSL/test/test_ssl.py
@@ -1233,7 +1233,7 @@
         context = Context(TLSv1_METHOD)
         try:
             context._set_tmp_ecdh_curve_by_nid(
-                u"curve", _lib.OBJ_sn2nid(b"sha256"))
+                u("curve"), _lib.OBJ_sn2nid(b"sha256"))
         except UnsupportedEllipticCurve:
             pass
         else: