add _testcapi.raise_memoryerror to make test_exceptions.test_MemoryError simpler
diff --git a/Lib/test/test_exceptions.py b/Lib/test/test_exceptions.py
index 95c2dd1..5ce76f1 100644
--- a/Lib/test/test_exceptions.py
+++ b/Lib/test/test_exceptions.py
@@ -593,9 +593,10 @@
         # PyErr_NoMemory always raises the same exception instance.
         # Check that the traceback is not doubled.
         import traceback
+        from _testcapi import raise_memoryerror
         def raiseMemError():
             try:
-                "a" * (sys.maxsize // 2)
+                raise_memoryerror()
             except MemoryError as e:
                 tb = e.__traceback__
             else:
diff --git a/Modules/_testcapimodule.c b/Modules/_testcapimodule.c
index 3ee3bf4..494937a 100644
--- a/Modules/_testcapimodule.c
+++ b/Modules/_testcapimodule.c
@@ -971,8 +971,19 @@
 
 
 
+
+/* reliably raise a MemoryError */
+static PyObject *
+raise_memoryerror(PyObject *self)
+{
+	PyErr_NoMemory();
+	return NULL;
+}
+
+
 static PyMethodDef TestMethods[] = {
 	{"raise_exception",	raise_exception,		 METH_VARARGS},
+	{"raise_memoryerror",   (PyCFunction)raise_memoryerror,  METH_NOARGS},
 	{"test_config",		(PyCFunction)test_config,	 METH_NOARGS},
 	{"test_list_api",	(PyCFunction)test_list_api,	 METH_NOARGS},
 	{"test_dict_iteration",	(PyCFunction)test_dict_iteration,METH_NOARGS},