1 files changed, 15 insertions, 1 deletions
diff --git a/Modules/_threadmodule.c b/Modules/_threadmodule.c
index 5edb6e9..568fe83 100644
--- a/Modules/_threadmodule.c
+++ b/Modules/_threadmodule.c
@@ -1604,6 +1604,18 @@ PyDoc_STRVAR(excepthook_doc,
 \n\
 Handle uncaught Thread.run() exception.");
 
+static PyObject *
+thread__is_main_interpreter(PyObject *module, PyObject *Py_UNUSED(ignored))
+{
+    PyInterpreterState *interp = _PyInterpreterState_GET();
+    return PyBool_FromLong(_Py_IsMainInterpreter(interp));
+}
+
+PyDoc_STRVAR(thread__is_main_interpreter_doc,
+"_is_main_interpreter()\n\
+\n\
+Return True if the current interpreter is the main Python interpreter.");
+
 static PyMethodDef thread_methods[] = {
     {"start_new_thread",        (PyCFunction)thread_PyThread_start_new_thread,
      METH_VARARGS, start_new_doc},
@@ -1633,8 +1645,10 @@ static PyMethodDef thread_methods[] = {
      METH_VARARGS, stack_size_doc},
     {"_set_sentinel",           thread__set_sentinel,
      METH_NOARGS, _set_sentinel_doc},
-    {"_excepthook",              thread_excepthook,
+    {"_excepthook",             thread_excepthook,
      METH_O, excepthook_doc},
+    {"_is_main_interpreter",    thread__is_main_interpreter,
+     METH_NOARGS, thread__is_main_interpreter_doc},
     {NULL,                      NULL}           /* sentinel */
 };