I chose to exclude setup.py changes from my commit 8510f430781118d9b603c3a2f06945d6ebc5fe42, whereas the Fedora downstream patch has a few changes:
https://src.fedoraproject.org/rpms/python39/blob/master/f/00102-lib64.patch

See also bpo-14791: "setup.py only adds /prefix/lib, not /prefix/lib64".

diff --git a/setup.py b/setup.py
index 51e67fe4a5..bafa0bf99a 100644
--- a/setup.py
+++ b/setup.py
@@ -649,7 +649,7 @@ class PyBuildExt(build_ext):
         # directories (i.e. '.' and 'Include') must be first.  See issue
         # 10520.
         if not CROSS_COMPILING:
-            add_dir_to_list(self.compiler.library_dirs, '/usr/local/lib')
+            add_dir_to_list(self.compiler.library_dirs, '/usr/local/lib64')
             add_dir_to_list(self.compiler.include_dirs, '/usr/local/include')
         # only change this for cross builds for 3.3, issues on Mageia
         if CROSS_COMPILING:
@@ -955,11 +955,11 @@ class PyBuildExt(build_ext):
             elif curses_library:
                 readline_libs.append(curses_library)
             elif self.compiler.find_library_file(self.lib_dirs +
-                                                     ['/usr/lib/termcap'],
+                                                     ['/usr/lib64/termcap'],
                                                      'termcap'):
                 readline_libs.append('termcap')
             self.add(Extension('readline', ['readline.c'],
-                               library_dirs=['/usr/lib/termcap'],
+                               library_dirs=['/usr/lib64/termcap'],
                                extra_link_args=readline_extra_link_args,
                                libraries=readline_libs))
         else: