1 files changed, 21 insertions, 11 deletions

diff --git a/Objects/genobject.c b/Objects/genobject.c
index f0943ae847..c1b26e9da3 100644
--- a/Objects/genobject.c
+++ b/Objects/genobject.c
@@ -269,13 +269,29 @@ gen_send_ex2(PyGenObject *gen, PyObject *arg, PyObject **presult,
 }
 
 PySendResult
-PyGen_Send(PyGenObject *gen, PyObject *arg, PyObject **result)
+PyIter_Send(PyObject *iter, PyObject *arg, PyObject **result)
 {
-    assert(PyGen_CheckExact(gen) || PyCoro_CheckExact(gen));
-    assert(result != NULL);
+    _Py_IDENTIFIER(send);
     assert(arg != NULL);
+    assert(result != NULL);
 
-    return gen_send_ex2(gen, arg, result, 0, 0);
+    if (PyGen_CheckExact(iter) || PyCoro_CheckExact(iter)) {
+        return gen_send_ex2((PyGenObject *)iter, arg, result, 0, 0);
+    }
+
+    if (arg == Py_None && PyIter_Check(iter)) {
+        *result = Py_TYPE(iter)->tp_iternext(iter);
+    }
+    else {
+        *result = _PyObject_CallMethodIdOneArg(iter, &PyId_send, arg);
+    }
+    if (*result != NULL) {
+        return PYGEN_NEXT;
+    }
+    if (_PyGen_FetchStopIterationValue(result) == 0) {
+        return PYGEN_RETURN;
+    }
+    return PYGEN_ERROR;
 }
 
 static PyObject *
@@ -308,12 +324,6 @@ gen_send(PyGenObject *gen, PyObject *arg)
     return gen_send_ex(gen, arg, 0, 0);
 }
 
-PyObject *
-_PyGen_Send(PyGenObject *gen, PyObject *arg)
-{
-    return gen_send(gen, arg);
-}
-
 PyDoc_STRVAR(close_doc,
 "close() -> raise GeneratorExit inside generator.");
 
@@ -1012,7 +1022,7 @@ PyDoc_STRVAR(coro_close_doc,
 "close() -> raise GeneratorExit inside coroutine.");
 
 static PyMethodDef coro_methods[] = {
-    {"send",(PyCFunction)_PyGen_Send, METH_O, coro_send_doc},
+    {"send",(PyCFunction)gen_send, METH_O, coro_send_doc},
     {"throw",(PyCFunction)gen_throw, METH_VARARGS, coro_throw_doc},
     {"close",(PyCFunction)gen_close, METH_NOARGS, coro_close_doc},
     {NULL, NULL}        /* Sentinel */