[MacPorts] #64916: Pythons 3.x for ppc+ppc64 on Leopard: No module named 'msvcrt', '_posixsubprocess' errors, how to fix?

[MacPorts]

#64916: Pythons 3.x for ppc+ppc64 on Leopard: No module named 'msvcrt',
'_posixsubprocess' errors, how to fix?
--------------------------------------------+------------------------------
  Reporter:  barracuda156                   |      Owner:  jmroot
      Type:  defect                         |     Status:  assigned
  Priority:  Normal                         |  Milestone:
 Component:  ports                          |    Version:  2.7.2
Resolution:                                 |   Keywords:  powerpc,
      Port:  python38, python39, python310  |  leopard, ppc64
--------------------------------------------+------------------------------

Comment (by barracuda156):

 UPD. I have also tried now to use approach from `python27`, changing
 relevant section in `python39` portfile to:

 {{{
 variant universal {
         patchfiles-append  patch-universal-powerpc.diff
     post-patch {
         reinplace \
             "s|__UNIVERSAL_ARCHFLAGS__|${configure.universal_cflags}|" \
             ${worksrcpath}/configure
     }
     if {${configure.sdkroot} ne ""} {
         configure.args-append   --enable-universalsdk=${configure.sdkroot}
     } else {
         configure.args-append   --enable-universalsdk=/
     }
     post-configure {
         set oldmtime [file mtime ${worksrcpath}/pyconfig.h]
         system -W ${worksrcpath} "ed - pyconfig.h <
 ${filespath}/pyconfig.h-universal.ed"
         file mtime ${worksrcpath}/pyconfig.h $oldmtime
     }

     post-destroot {
         foreach unversioned {python3-32 python3-intel64} {
             delete ${destroot}${prefix}/bin/${unversioned}
         }
     }
 }
 }}}

 And then modifying patches; build itself again was successful, but trying
 to install any modules again fails:

 {{{
 --->  Building py39-curl
 Traceback (most recent call last):
   File
 "/opt/local/Library/Frameworks/Python.framework/Versions/3.9/lib/python3.9/subprocess.py",
 line 73, in <module>
     import msvcrt
 ModuleNotFoundError: No module named 'msvcrt'

 During handling of the above exception, another exception occurred:

 Traceback (most recent call last):
   File
 "/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports
 .org_macports_release_tarballs_ports_python_py-
 curl/py39-curl/work/pycurl-7.44.1/setup.py", line 11, in <module>
     import glob, os, re, sys, subprocess
   File
 "/opt/local/Library/Frameworks/Python.framework/Versions/3.9/lib/python3.9/subprocess.py",
 line 78, in <module>
     import _posixsubprocess
 ModuleNotFoundError: No module named '_posixsubprocess'
 Command failed:
 /opt/local/Library/Frameworks/Python.framework/Versions/3.9/bin/python3.9
 setup.py docstrings
 Exit code: 1
 Error: Failed to build py39-curl: command execution failed
 }}}

-- 
Ticket URL: <https://trac.macports.org/ticket/64916#comment:3>
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