diff --git a/Modules/_ssl.c b/Modules/_ssl.c
index 9bd0776..c27073c 100644
--- a/Modules/_ssl.c
+++ b/Modules/_ssl.c
@@ -3588,7 +3588,7 @@
     PyObject *keyusage = NULL, *cert = NULL, *enc = NULL, *tup = NULL;
     PyObject *result = NULL;
 
-    if (!PyArg_ParseTupleAndKeywords(args, kwds, "s|s:enum_certificates",
+    if (!PyArg_ParseTupleAndKeywords(args, kwds, "s:enum_certificates",
                                      kwlist, &store_name)) {
         return NULL;
     }
@@ -3676,7 +3676,7 @@
     PyObject *crl = NULL, *enc = NULL, *tup = NULL;
     PyObject *result = NULL;
 
-    if (!PyArg_ParseTupleAndKeywords(args, kwds, "s|s:enum_crls",
+    if (!PyArg_ParseTupleAndKeywords(args, kwds, "s:enum_crls",
                                      kwlist, &store_name)) {
         return NULL;
     }