bpo-40268: Include explicitly pycore_interp.h (GH-19505)
pycore_pystate.h no longer includes pycore_interp.h:
it's now included explicitly in files accessing PyInterpreterState.
diff --git a/Python/sysmodule.c b/Python/sysmodule.c
index fd0a9c0..814e4ab 100644
--- a/Python/sysmodule.c
+++ b/Python/sysmodule.c
@@ -17,7 +17,9 @@
#include "Python.h"
#include "code.h"
#include "frameobject.h"
-#include "pycore_ceval.h"
+#include "pycore_ceval.h" // _Py_RecursionLimitLowerWaterMark()
+#include "pycore_pystate.h" // _PyThreadState_GET()
+#include "pycore_tupleobject.h"
#include "pycore_initconfig.h"
#include "pycore_pathconfig.h"
#include "pycore_pyerrors.h"