--- exec.cpp.orig	2019-12-10 01:19:39.000000000 +0100
+++ exec.cpp	2021-11-25 11:11:49.933084600 +0100
@@ -104,9 +104,16 @@
   if (local.is_none()) local = global;
   // should be 'char const *' but older python versions don't use 'const' yet.
   char *f = const_cast<char *>(filename);
-  // Let python open the file to avoid potential binary incompatibilities.
-#if PY_VERSION_HEX >= 0x03040000
-  FILE *fs = _Py_fopen(f, "r");
+#if PY_VERSION_HEX >= 0x03010000
+  // Backported from Boost.Python v1.75.0 to build LuxCore for Python 3.10
+  // Let python manage any UTF bits to avoid potential incompatibilities.
+  PyObject *fo = Py_BuildValue("s", f);
+  PyObject *fb = Py_None;
+  PyUnicode_FSConverter(fo, &fb);
+  f = PyBytes_AsString(fb);
+  FILE *fs = fopen(f, "r");
+  Py_DECREF(fo);
+  Py_DECREF(fb);
 #elif PY_VERSION_HEX >= 0x03000000
   PyObject *fo = Py_BuildValue("s", f);
   FILE *fs = _Py_fopen(fo, "r");