Only in python3: autom4te.cache
diff -urp '--exclude=*~' '--exclude=config.*' '--exclude=configure' '--exclude=Makefile' '--exclude=autom4te' python3.orig/configure.ac python3/configure.ac
--- python3.orig/configure.ac	2023-01-02 12:09:13.189241055 +0900
+++ python3/configure.ac	2023-01-02 12:54:23.110443109 +0900
@@ -626,6 +626,7 @@ if test "$PYTHON" != "false"; then
    dnl DO NOT ASK WHY. I too can't explain.
    python_version=`(LANG=C ${PYTHON} --version 2>&1 | ${PERL} -e '$vin=<>;printf "python%s",substr($vin,7,rindex($vin,"\.",20)-7);')`
    AC_MSG_RESULT($python_version)
+   python3_minor=`(echo ${python_version} | sed -e 's|python3\.||')`
    python_config_bin=${python_version}-config
    python_configm_bin=${python_version}m-config
    python_configmu_bin=${python_version}mu-config
@@ -650,6 +651,13 @@ if test "$PYTHON" != "false"; then
 
     dnl  python 3.0, 3.1 & 3.2 are obsoleted and not supported
 	if test "$enable_python3" = "yes";then
+		 AC_MSG_CHECKING([whether python3 uses PEP 623])
+		 if test "$python3_minor" -ge 10 ; then
+		    AC_MSG_RESULT([yes])
+		    python_define="$python_define -DUSE_PEP623"
+		 else
+		    AC_MSG_RESULT([yes])
+		 fi
 		 python_define="$python_define -DUSE_PEP393"
 	 fi
        
diff -urp '--exclude=*~' '--exclude=config.*' '--exclude=configure' '--exclude=Makefile' '--exclude=autom4te' python3.orig/skf_convert.i python3/skf_convert.i
--- python3.orig/skf_convert.i	2022-11-13 01:58:54.000000000 +0900
+++ python3/skf_convert.i	2023-01-02 14:05:06.713513508 +0900
@@ -106,10 +106,16 @@ const char *skf_notstring = "skf: not st
 #include "unicodeobject.h"
 #include "bytearrayobject.h"
 #define	Py_SKFSTR	PyObject
-#ifdef USE_PEP393		/* after python 3.3 */
+#if defined (USE_PEP623) /* after python 3.10 */
+#define skf_PyUnicode_Srctype Py_UCS4
+#define skf_PyUnicode_GetSize(x) PyUnicode_GET_LENGTH(x) 
+#define skf_PyUnicode_AsUnicode(x) PyUnicode_AsUCS4Copy(x)	
+#elif defined (USE_PEP393)		/* after python 3.3 */
+#define skf_PyUnicode_Srctype Py_UNICODE
 #define skf_PyUnicode_GetSize(x) PyUnicode_GET_LENGTH(x) 
 #define skf_PyUnicode_AsUnicode(x) PyUnicode_AS_UNICODE(x)	
 #else	/* NOT PEP393 */
+#define skf_PyUnicode_Srctype Py_UNICODE
 #define skf_PyUnicode_GetSize	PyUnicode_GETSIZE
 #define skf_PyUnicode_AsUnicode	PyUnicode_AsUnicode
 #endif
@@ -434,7 +440,7 @@ int	c;
 char	*skfstrstrconv(PyObject *robj,size_t len)
 {
     char	*dstr;
-    Py_UNICODE	*srcstr;
+    skf_PyUnicode_Srctype	*srcstr = NULL;
     char	*bsrcstr;
     Py_ssize_t	slen;
     int		i;
@@ -467,6 +473,9 @@ char	*skfstrstrconv(PyObject *robj,size_
 	    if (srcstr[i] >= 0x7f) break;
 	    dstr[i] = srcstr[i];
 	};
+#if defined (USE_PEP623)
+      PyMem_Free(srcstr);
+#endif
     } else if (PyByteArray_Check(robj)) { /* if SANE object	   */
         if ((slen = PyByteArray_Size(robj)) <= 0) {
 	    return(NULL);