bpo-35489: Use "const Py_UNICODE *" for the Py_UNICODE converter in AC. (GH-11150)

diff --git a/Modules/clinic/posixmodule.c.h b/Modules/clinic/posixmodule.c.h
index 8069070..6d523bc 100644
--- a/Modules/clinic/posixmodule.c.h
+++ b/Modules/clinic/posixmodule.c.h
@@ -1329,7 +1329,7 @@
     {"system", (PyCFunction)(void(*)(void))os_system, METH_FASTCALL|METH_KEYWORDS, os_system__doc__},
 
 static long
-os_system_impl(PyObject *module, Py_UNICODE *command);
+os_system_impl(PyObject *module, const Py_UNICODE *command);
 
 static PyObject *
 os_system(PyObject *module, PyObject *const *args, Py_ssize_t nargs, PyObject *kwnames)
@@ -1337,7 +1337,7 @@
     PyObject *return_value = NULL;
     static const char * const _keywords[] = {"command", NULL};
     static _PyArg_Parser _parser = {"u:system", _keywords, 0};
-    Py_UNICODE *command;
+    const Py_UNICODE *command;
     long _return_value;
 
     if (!_PyArg_ParseStackAndKeywords(args, nargs, kwnames, &_parser,
@@ -5327,7 +5327,8 @@
     {"startfile", (PyCFunction)(void(*)(void))os_startfile, METH_FASTCALL|METH_KEYWORDS, os_startfile__doc__},
 
 static PyObject *
-os_startfile_impl(PyObject *module, path_t *filepath, Py_UNICODE *operation);
+os_startfile_impl(PyObject *module, path_t *filepath,
+                  const Py_UNICODE *operation);
 
 static PyObject *
 os_startfile(PyObject *module, PyObject *const *args, Py_ssize_t nargs, PyObject *kwnames)
@@ -5336,7 +5337,7 @@
     static const char * const _keywords[] = {"filepath", "operation", NULL};
     static _PyArg_Parser _parser = {"O&|u:startfile", _keywords, 0};
     path_t filepath = PATH_T_INITIALIZE("startfile", "filepath", 0, 0);
-    Py_UNICODE *operation = NULL;
+    const Py_UNICODE *operation = NULL;
 
     if (!_PyArg_ParseStackAndKeywords(args, nargs, kwnames, &_parser,
         path_converter, &filepath, &operation)) {
@@ -6757,4 +6758,4 @@
 #ifndef OS_GETRANDOM_METHODDEF
     #define OS_GETRANDOM_METHODDEF
 #endif /* !defined(OS_GETRANDOM_METHODDEF) */
-/*[clinic end generated code: output=d62c0bb988141e70 input=a9049054013a1b77]*/
+/*[clinic end generated code: output=7ebb53d872bab149 input=a9049054013a1b77]*/