Library import 16 (#2433)

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diff --git a/contrib/tools/python3/Lib/platform.py b/contrib/tools/python3/Lib/platform.py
new file mode 100755
index 0000000000..7bb222088d
--- /dev/null
+++ b/contrib/tools/python3/Lib/platform.py
@@ -0,0 +1,1357 @@
+#!/usr/bin/env python3
+
+""" This module tries to retrieve as much platform-identifying data as
+    possible. It makes this information available via function APIs.
+
+    If called from the command line, it prints the platform
+    information concatenated as single string to stdout. The output
+    format is usable as part of a filename.
+
+"""
+#    This module is maintained by Marc-Andre Lemburg <mal@egenix.com>.
+#    If you find problems, please submit bug reports/patches via the
+#    Python bug tracker (http://bugs.python.org) and assign them to "lemburg".
+#
+#    Still needed:
+#    * support for MS-DOS (PythonDX ?)
+#    * support for Amiga and other still unsupported platforms running Python
+#    * support for additional Linux distributions
+#
+#    Many thanks to all those who helped adding platform-specific
+#    checks (in no particular order):
+#
+#      Charles G Waldman, David Arnold, Gordon McMillan, Ben Darnell,
+#      Jeff Bauer, Cliff Crawford, Ivan Van Laningham, Josef
+#      Betancourt, Randall Hopper, Karl Putland, John Farrell, Greg
+#      Andruk, Just van Rossum, Thomas Heller, Mark R. Levinson, Mark
+#      Hammond, Bill Tutt, Hans Nowak, Uwe Zessin (OpenVMS support),
+#      Colin Kong, Trent Mick, Guido van Rossum, Anthony Baxter, Steve
+#      Dower
+#
+#    History:
+#
+#    <see CVS and SVN checkin messages for history>
+#
+#    1.0.8 - changed Windows support to read version from kernel32.dll
+#    1.0.7 - added DEV_NULL
+#    1.0.6 - added linux_distribution()
+#    1.0.5 - fixed Java support to allow running the module on Jython
+#    1.0.4 - added IronPython support
+#    1.0.3 - added normalization of Windows system name
+#    1.0.2 - added more Windows support
+#    1.0.1 - reformatted to make doc.py happy
+#    1.0.0 - reformatted a bit and checked into Python CVS
+#    0.8.0 - added sys.version parser and various new access
+#            APIs (python_version(), python_compiler(), etc.)
+#    0.7.2 - fixed architecture() to use sizeof(pointer) where available
+#    0.7.1 - added support for Caldera OpenLinux
+#    0.7.0 - some fixes for WinCE; untabified the source file
+#    0.6.2 - support for OpenVMS - requires version 1.5.2-V006 or higher and
+#            vms_lib.getsyi() configured
+#    0.6.1 - added code to prevent 'uname -p' on platforms which are
+#            known not to support it
+#    0.6.0 - fixed win32_ver() to hopefully work on Win95,98,NT and Win2k;
+#            did some cleanup of the interfaces - some APIs have changed
+#    0.5.5 - fixed another type in the MacOS code... should have
+#            used more coffee today ;-)
+#    0.5.4 - fixed a few typos in the MacOS code
+#    0.5.3 - added experimental MacOS support; added better popen()
+#            workarounds in _syscmd_ver() -- still not 100% elegant
+#            though
+#    0.5.2 - fixed uname() to return '' instead of 'unknown' in all
+#            return values (the system uname command tends to return
+#            'unknown' instead of just leaving the field empty)
+#    0.5.1 - included code for slackware dist; added exception handlers
+#            to cover up situations where platforms don't have os.popen
+#            (e.g. Mac) or fail on socket.gethostname(); fixed libc
+#            detection RE
+#    0.5.0 - changed the API names referring to system commands to *syscmd*;
+#            added java_ver(); made syscmd_ver() a private
+#            API (was system_ver() in previous versions) -- use uname()
+#            instead; extended the win32_ver() to also return processor
+#            type information
+#    0.4.0 - added win32_ver() and modified the platform() output for WinXX
+#    0.3.4 - fixed a bug in _follow_symlinks()
+#    0.3.3 - fixed popen() and "file" command invocation bugs
+#    0.3.2 - added architecture() API and support for it in platform()
+#    0.3.1 - fixed syscmd_ver() RE to support Windows NT
+#    0.3.0 - added system alias support
+#    0.2.3 - removed 'wince' again... oh well.
+#    0.2.2 - added 'wince' to syscmd_ver() supported platforms
+#    0.2.1 - added cache logic and changed the platform string format
+#    0.2.0 - changed the API to use functions instead of module globals
+#            since some action take too long to be run on module import
+#    0.1.0 - first release
+#
+#    You can always get the latest version of this module at:
+#
+#             http://www.egenix.com/files/python/platform.py
+#
+#    If that URL should fail, try contacting the author.
+
+__copyright__ = """
+    Copyright (c) 1999-2000, Marc-Andre Lemburg; mailto:mal@lemburg.com
+    Copyright (c) 2000-2010, eGenix.com Software GmbH; mailto:info@egenix.com
+
+    Permission to use, copy, modify, and distribute this software and its
+    documentation for any purpose and without fee or royalty is hereby granted,
+    provided that the above copyright notice appear in all copies and that
+    both that copyright notice and this permission notice appear in
+    supporting documentation or portions thereof, including modifications,
+    that you make.
+
+    EGENIX.COM SOFTWARE GMBH DISCLAIMS ALL WARRANTIES WITH REGARD TO
+    THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
+    FITNESS, IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL,
+    INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING
+    FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
+    NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
+    WITH THE USE OR PERFORMANCE OF THIS SOFTWARE !
+
+"""
+
+__version__ = '1.0.8'
+
+import collections
+import os
+import re
+import sys
+import functools
+import itertools
+
+### Globals & Constants
+
+# Helper for comparing two version number strings.
+# Based on the description of the PHP's version_compare():
+# http://php.net/manual/en/function.version-compare.php
+
+_ver_stages = {
+    # any string not found in this dict, will get 0 assigned
+    'dev': 10,
+    'alpha': 20, 'a': 20,
+    'beta': 30, 'b': 30,
+    'c': 40,
+    'RC': 50, 'rc': 50,
+    # number, will get 100 assigned
+    'pl': 200, 'p': 200,
+}
+
+
+def _comparable_version(version):
+    component_re = re.compile(r'([0-9]+|[._+-])')
+    result = []
+    for v in component_re.split(version):
+        if v not in '._+-':
+            try:
+                v = int(v, 10)
+                t = 100
+            except ValueError:
+                t = _ver_stages.get(v, 0)
+            result.extend((t, v))
+    return result
+
+### Platform specific APIs
+
+
+def libc_ver(executable=None, lib='', version='', chunksize=16384):
+
+    """ Tries to determine the libc version that the file executable
+        (which defaults to the Python interpreter) is linked against.
+
+        Returns a tuple of strings (lib,version) which default to the
+        given parameters in case the lookup fails.
+
+        Note that the function has intimate knowledge of how different
+        libc versions add symbols to the executable and thus is probably
+        only usable for executables compiled using gcc.
+
+        The file is read and scanned in chunks of chunksize bytes.
+
+    """
+    if not executable:
+        try:
+            ver = os.confstr('CS_GNU_LIBC_VERSION')
+            # parse 'glibc 2.28' as ('glibc', '2.28')
+            parts = ver.split(maxsplit=1)
+            if len(parts) == 2:
+                return tuple(parts)
+        except (AttributeError, ValueError, OSError):
+            # os.confstr() or CS_GNU_LIBC_VERSION value not available
+            pass
+
+        executable = sys.executable
+
+        if not executable:
+            # sys.executable is not set.
+            return lib, version
+
+    libc_search = re.compile(b'(__libc_init)'
+                          b'|'
+                          b'(GLIBC_([0-9.]+))'
+                          b'|'
+                          br'(libc(_\w+)?\.so(?:\.(\d[0-9.]*))?)', re.ASCII)
+
+    V = _comparable_version
+    # We use os.path.realpath()
+    # here to work around problems with Cygwin not being
+    # able to open symlinks for reading
+    executable = os.path.realpath(executable)
+    with open(executable, 'rb') as f:
+        binary = f.read(chunksize)
+        pos = 0
+        while pos < len(binary):
+            if b'libc' in binary or b'GLIBC' in binary:
+                m = libc_search.search(binary, pos)
+            else:
+                m = None
+            if not m or m.end() == len(binary):
+                chunk = f.read(chunksize)
+                if chunk:
+                    binary = binary[max(pos, len(binary) - 1000):] + chunk
+                    pos = 0
+                    continue
+                if not m:
+                    break
+            libcinit, glibc, glibcversion, so, threads, soversion = [
+                s.decode('latin1') if s is not None else s
+                for s in m.groups()]
+            if libcinit and not lib:
+                lib = 'libc'
+            elif glibc:
+                if lib != 'glibc':
+                    lib = 'glibc'
+                    version = glibcversion
+                elif V(glibcversion) > V(version):
+                    version = glibcversion
+            elif so:
+                if lib != 'glibc':
+                    lib = 'libc'
+                    if soversion and (not version or V(soversion) > V(version)):
+                        version = soversion
+                    if threads and version[-len(threads):] != threads:
+                        version = version + threads
+            pos = m.end()
+    return lib, version
+
+def _norm_version(version, build=''):
+
+    """ Normalize the version and build strings and return a single
+        version string using the format major.minor.build (or patchlevel).
+    """
+    l = version.split('.')
+    if build:
+        l.append(build)
+    try:
+        strings = list(map(str, map(int, l)))
+    except ValueError:
+        strings = l
+    version = '.'.join(strings[:3])
+    return version
+
+
+# Examples of VER command output:
+#
+#   Windows 2000:  Microsoft Windows 2000 [Version 5.00.2195]
+#   Windows XP:    Microsoft Windows XP [Version 5.1.2600]
+#   Windows Vista: Microsoft Windows [Version 6.0.6002]
+#
+# Note that the "Version" string gets localized on different
+# Windows versions.
+
+def _syscmd_ver(system='', release='', version='',
+
+               supported_platforms=('win32', 'win16', 'dos')):
+
+    """ Tries to figure out the OS version used and returns
+        a tuple (system, release, version).
+
+        It uses the "ver" shell command for this which is known
+        to exists on Windows, DOS. XXX Others too ?
+
+        In case this fails, the given parameters are used as
+        defaults.
+
+    """
+    if sys.platform not in supported_platforms:
+        return system, release, version
+
+    # Try some common cmd strings
+    import subprocess
+    for cmd in ('ver', 'command /c ver', 'cmd /c ver'):
+        try:
+            info = subprocess.check_output(cmd,
+                                           stdin=subprocess.DEVNULL,
+                                           stderr=subprocess.DEVNULL,
+                                           text=True,
+                                           encoding="locale",
+                                           shell=True)
+        except (OSError, subprocess.CalledProcessError) as why:
+            #print('Command %s failed: %s' % (cmd, why))
+            continue
+        else:
+            break
+    else:
+        return system, release, version
+
+    ver_output = re.compile(r'(?:([\w ]+) ([\w.]+) '
+                         r'.*'
+                         r'\[.* ([\d.]+)\])')
+
+    # Parse the output
+    info = info.strip()
+    m = ver_output.match(info)
+    if m is not None:
+        system, release, version = m.groups()
+        # Strip trailing dots from version and release
+        if release[-1] == '.':
+            release = release[:-1]
+        if version[-1] == '.':
+            version = version[:-1]
+        # Normalize the version and build strings (eliminating additional
+        # zeros)
+        version = _norm_version(version)
+    return system, release, version
+
+try:
+    import _wmi
+except ImportError:
+    def _wmi_query(*keys):
+        raise OSError("not supported")
+else:
+    def _wmi_query(table, *keys):
+        table = {
+            "OS": "Win32_OperatingSystem",
+            "CPU": "Win32_Processor",
+        }[table]
+        data = _wmi.exec_query("SELECT {} FROM {}".format(
+            ",".join(keys),
+            table,
+        )).split("\0")
+        split_data = (i.partition("=") for i in data)
+        dict_data = {i[0]: i[2] for i in split_data}
+        return (dict_data[k] for k in keys)
+
+
+_WIN32_CLIENT_RELEASES = [
+    ((10, 1, 0), "post11"),
+    ((10, 0, 22000), "11"),
+    ((6, 4, 0), "10"),
+    ((6, 3, 0), "8.1"),
+    ((6, 2, 0), "8"),
+    ((6, 1, 0), "7"),
+    ((6, 0, 0), "Vista"),
+    ((5, 2, 3790), "XP64"),
+    ((5, 2, 0), "XPMedia"),
+    ((5, 1, 0), "XP"),
+    ((5, 0, 0), "2000"),
+]
+
+_WIN32_SERVER_RELEASES = [
+    ((10, 1, 0), "post2022Server"),
+    ((10, 0, 20348), "2022Server"),
+    ((10, 0, 17763), "2019Server"),
+    ((6, 4, 0), "2016Server"),
+    ((6, 3, 0), "2012ServerR2"),
+    ((6, 2, 0), "2012Server"),
+    ((6, 1, 0), "2008ServerR2"),
+    ((6, 0, 0), "2008Server"),
+    ((5, 2, 0), "2003Server"),
+    ((5, 0, 0), "2000Server"),
+]
+
+def win32_is_iot():
+    return win32_edition() in ('IoTUAP', 'NanoServer', 'WindowsCoreHeadless', 'IoTEdgeOS')
+
+def win32_edition():
+    try:
+        try:
+            import winreg
+        except ImportError:
+            import _winreg as winreg
+    except ImportError:
+        pass
+    else:
+        try:
+            cvkey = r'SOFTWARE\Microsoft\Windows NT\CurrentVersion'
+            with winreg.OpenKeyEx(winreg.HKEY_LOCAL_MACHINE, cvkey) as key:
+                return winreg.QueryValueEx(key, 'EditionId')[0]
+        except OSError:
+            pass
+
+    return None
+
+def _win32_ver(version, csd, ptype):
+    # Try using WMI first, as this is the canonical source of data
+    try:
+        (version, product_type, ptype, spmajor, spminor)  = _wmi_query(
+            'OS',
+            'Version',
+            'ProductType',
+            'BuildType',
+            'ServicePackMajorVersion',
+            'ServicePackMinorVersion',
+        )
+        is_client = (int(product_type) == 1)
+        if spminor and spminor != '0':
+            csd = f'SP{spmajor}.{spminor}'
+        else:
+            csd = f'SP{spmajor}'
+        return version, csd, ptype, is_client
+    except OSError:
+        pass
+
+    # Fall back to a combination of sys.getwindowsversion and "ver"
+    try:
+        from sys import getwindowsversion
+    except ImportError:
+        return version, csd, ptype, True
+
+    winver = getwindowsversion()
+    is_client = (getattr(winver, 'product_type', 1) == 1)
+    try:
+        version = _syscmd_ver()[2]
+        major, minor, build = map(int, version.split('.'))
+    except ValueError:
+        major, minor, build = winver.platform_version or winver[:3]
+        version = '{0}.{1}.{2}'.format(major, minor, build)
+
+    # getwindowsversion() reflect the compatibility mode Python is
+    # running under, and so the service pack value is only going to be
+    # valid if the versions match.
+    if winver[:2] == (major, minor):
+        try:
+            csd = 'SP{}'.format(winver.service_pack_major)
+        except AttributeError:
+            if csd[:13] == 'Service Pack ':
+                csd = 'SP' + csd[13:]
+
+    try:
+        try:
+            import winreg
+        except ImportError:
+            import _winreg as winreg
+    except ImportError:
+        pass
+    else:
+        try:
+            cvkey = r'SOFTWARE\Microsoft\Windows NT\CurrentVersion'
+            with winreg.OpenKeyEx(winreg.HKEY_LOCAL_MACHINE, cvkey) as key:
+                ptype = winreg.QueryValueEx(key, 'CurrentType')[0]
+        except OSError:
+            pass
+
+    return version, csd, ptype, is_client
+
+def win32_ver(release='', version='', csd='', ptype=''):
+    is_client = False
+
+    version, csd, ptype, is_client = _win32_ver(version, csd, ptype)
+
+    if version:
+        intversion = tuple(map(int, version.split('.')))
+        releases = _WIN32_CLIENT_RELEASES if is_client else _WIN32_SERVER_RELEASES
+        release = next((r for v, r in releases if v <= intversion), release)
+
+    return release, version, csd, ptype
+
+
+def _mac_ver_xml():
+    fn = '/System/Library/CoreServices/SystemVersion.plist'
+    if not os.path.exists(fn):
+        return None
+
+    try:
+        import plistlib
+    except ImportError:
+        return None
+
+    with open(fn, 'rb') as f:
+        pl = plistlib.load(f)
+    release = pl['ProductVersion']
+    versioninfo = ('', '', '')
+    machine = os.uname().machine
+    if machine in ('ppc', 'Power Macintosh'):
+        # Canonical name
+        machine = 'PowerPC'
+
+    return release, versioninfo, machine
+
+
+def mac_ver(release='', versioninfo=('', '', ''), machine=''):
+
+    """ Get macOS version information and return it as tuple (release,
+        versioninfo, machine) with versioninfo being a tuple (version,
+        dev_stage, non_release_version).
+
+        Entries which cannot be determined are set to the parameter values
+        which default to ''. All tuple entries are strings.
+    """
+
+    # First try reading the information from an XML file which should
+    # always be present
+    info = _mac_ver_xml()
+    if info is not None:
+        return info
+
+    # If that also doesn't work return the default values
+    return release, versioninfo, machine
+
+def _java_getprop(name, default):
+
+    from java.lang import System
+    try:
+        value = System.getProperty(name)
+        if value is None:
+            return default
+        return value
+    except AttributeError:
+        return default
+
+def java_ver(release='', vendor='', vminfo=('', '', ''), osinfo=('', '', '')):
+
+    """ Version interface for Jython.
+
+        Returns a tuple (release, vendor, vminfo, osinfo) with vminfo being
+        a tuple (vm_name, vm_release, vm_vendor) and osinfo being a
+        tuple (os_name, os_version, os_arch).
+
+        Values which cannot be determined are set to the defaults
+        given as parameters (which all default to '').
+
+    """
+    # Import the needed APIs
+    try:
+        import java.lang
+    except ImportError:
+        return release, vendor, vminfo, osinfo
+
+    vendor = _java_getprop('java.vendor', vendor)
+    release = _java_getprop('java.version', release)
+    vm_name, vm_release, vm_vendor = vminfo
+    vm_name = _java_getprop('java.vm.name', vm_name)
+    vm_vendor = _java_getprop('java.vm.vendor', vm_vendor)
+    vm_release = _java_getprop('java.vm.version', vm_release)
+    vminfo = vm_name, vm_release, vm_vendor
+    os_name, os_version, os_arch = osinfo
+    os_arch = _java_getprop('java.os.arch', os_arch)
+    os_name = _java_getprop('java.os.name', os_name)
+    os_version = _java_getprop('java.os.version', os_version)
+    osinfo = os_name, os_version, os_arch
+
+    return release, vendor, vminfo, osinfo
+
+### System name aliasing
+
+def system_alias(system, release, version):
+
+    """ Returns (system, release, version) aliased to common
+        marketing names used for some systems.
+
+        It also does some reordering of the information in some cases
+        where it would otherwise cause confusion.
+
+    """
+    if system == 'SunOS':
+        # Sun's OS
+        if release < '5':
+            # These releases use the old name SunOS
+            return system, release, version
+        # Modify release (marketing release = SunOS release - 3)
+        l = release.split('.')
+        if l:
+            try:
+                major = int(l[0])
+            except ValueError:
+                pass
+            else:
+                major = major - 3
+                l[0] = str(major)
+                release = '.'.join(l)
+        if release < '6':
+            system = 'Solaris'
+        else:
+            # XXX Whatever the new SunOS marketing name is...
+            system = 'Solaris'
+
+    elif system in ('win32', 'win16'):
+        # In case one of the other tricks
+        system = 'Windows'
+
+    # bpo-35516: Don't replace Darwin with macOS since input release and
+    # version arguments can be different than the currently running version.
+
+    return system, release, version
+
+### Various internal helpers
+
+def _platform(*args):
+
+    """ Helper to format the platform string in a filename
+        compatible format e.g. "system-version-machine".
+    """
+    # Format the platform string
+    platform = '-'.join(x.strip() for x in filter(len, args))
+
+    # Cleanup some possible filename obstacles...
+    platform = platform.replace(' ', '_')
+    platform = platform.replace('/', '-')
+    platform = platform.replace('\\', '-')
+    platform = platform.replace(':', '-')
+    platform = platform.replace(';', '-')
+    platform = platform.replace('"', '-')
+    platform = platform.replace('(', '-')
+    platform = platform.replace(')', '-')
+
+    # No need to report 'unknown' information...
+    platform = platform.replace('unknown', '')
+
+    # Fold '--'s and remove trailing '-'
+    while True:
+        cleaned = platform.replace('--', '-')
+        if cleaned == platform:
+            break
+        platform = cleaned
+    while platform[-1] == '-':
+        platform = platform[:-1]
+
+    return platform
+
+def _node(default=''):
+
+    """ Helper to determine the node name of this machine.
+    """
+    try:
+        import socket
+    except ImportError:
+        # No sockets...
+        return default
+    try:
+        return socket.gethostname()
+    except OSError:
+        # Still not working...
+        return default
+
+def _follow_symlinks(filepath):
+
+    """ In case filepath is a symlink, follow it until a
+        real file is reached.
+    """
+    filepath = os.path.abspath(filepath)
+    while os.path.islink(filepath):
+        filepath = os.path.normpath(
+            os.path.join(os.path.dirname(filepath), os.readlink(filepath)))
+    return filepath
+
+
+def _syscmd_file(target, default=''):
+
+    """ Interface to the system's file command.
+
+        The function uses the -b option of the file command to have it
+        omit the filename in its output. Follow the symlinks. It returns
+        default in case the command should fail.
+
+    """
+    if sys.platform in ('dos', 'win32', 'win16'):
+        # XXX Others too ?
+        return default
+
+    try:
+        import subprocess
+    except ImportError:
+        return default
+    target = _follow_symlinks(target)
+    # "file" output is locale dependent: force the usage of the C locale
+    # to get deterministic behavior.
+    env = dict(os.environ, LC_ALL='C')
+    try:
+        # -b: do not prepend filenames to output lines (brief mode)
+        output = subprocess.check_output(['file', '-b', target],
+                                         stderr=subprocess.DEVNULL,
+                                         env=env)
+    except (OSError, subprocess.CalledProcessError):
+        return default
+    if not output:
+        return default
+    # With the C locale, the output should be mostly ASCII-compatible.
+    # Decode from Latin-1 to prevent Unicode decode error.
+    return output.decode('latin-1')
+
+### Information about the used architecture
+
+# Default values for architecture; non-empty strings override the
+# defaults given as parameters
+_default_architecture = {
+    'win32': ('', 'WindowsPE'),
+    'win16': ('', 'Windows'),
+    'dos': ('', 'MSDOS'),
+}
+
+def architecture(executable=sys.executable, bits='', linkage=''):
+
+    """ Queries the given executable (defaults to the Python interpreter
+        binary) for various architecture information.
+
+        Returns a tuple (bits, linkage) which contains information about
+        the bit architecture and the linkage format used for the
+        executable. Both values are returned as strings.
+
+        Values that cannot be determined are returned as given by the
+        parameter presets. If bits is given as '', the sizeof(pointer)
+        (or sizeof(long) on Python version < 1.5.2) is used as
+        indicator for the supported pointer size.
+
+        The function relies on the system's "file" command to do the
+        actual work. This is available on most if not all Unix
+        platforms. On some non-Unix platforms where the "file" command
+        does not exist and the executable is set to the Python interpreter
+        binary defaults from _default_architecture are used.
+
+    """
+    # Use the sizeof(pointer) as default number of bits if nothing
+    # else is given as default.
+    if not bits:
+        import struct
+        size = struct.calcsize('P')
+        bits = str(size * 8) + 'bit'
+
+    # Get data from the 'file' system command
+    if executable:
+        fileout = _syscmd_file(executable, '')
+    else:
+        fileout = ''
+
+    if not fileout and \
+       executable == sys.executable:
+        # "file" command did not return anything; we'll try to provide
+        # some sensible defaults then...
+        if sys.platform in _default_architecture:
+            b, l = _default_architecture[sys.platform]
+            if b:
+                bits = b
+            if l:
+                linkage = l
+        return bits, linkage
+
+    if 'executable' not in fileout and 'shared object' not in fileout:
+        # Format not supported
+        return bits, linkage
+
+    # Bits
+    if '32-bit' in fileout:
+        bits = '32bit'
+    elif '64-bit' in fileout:
+        bits = '64bit'
+
+    # Linkage
+    if 'ELF' in fileout:
+        linkage = 'ELF'
+    elif 'PE' in fileout:
+        # E.g. Windows uses this format
+        if 'Windows' in fileout:
+            linkage = 'WindowsPE'
+        else:
+            linkage = 'PE'
+    elif 'COFF' in fileout:
+        linkage = 'COFF'
+    elif 'MS-DOS' in fileout:
+        linkage = 'MSDOS'
+    else:
+        # XXX the A.OUT format also falls under this class...
+        pass
+
+    return bits, linkage
+
+
+def _get_machine_win32():
+    # Try to use the PROCESSOR_* environment variables
+    # available on Win XP and later; see
+    # http://support.microsoft.com/kb/888731 and
+    # http://www.geocities.com/rick_lively/MANUALS/ENV/MSWIN/PROCESSI.HTM
+
+    # WOW64 processes mask the native architecture
+    try:
+        [arch, *_] = _wmi_query('CPU', 'Architecture')
+    except OSError:
+        pass
+    else:
+        try:
+            arch = ['x86', 'MIPS', 'Alpha', 'PowerPC', None,
+                    'ARM', 'ia64', None, None,
+                    'AMD64', None, None, 'ARM64',
+            ][int(arch)]
+        except (ValueError, IndexError):
+            pass
+        else:
+            if arch:
+                return arch
+    return (
+        os.environ.get('PROCESSOR_ARCHITEW6432', '') or
+        os.environ.get('PROCESSOR_ARCHITECTURE', '')
+    )
+
+
+class _Processor:
+    @classmethod
+    def get(cls):
+        func = getattr(cls, f'get_{sys.platform}', cls.from_subprocess)
+        return func() or ''
+
+    def get_win32():
+        try:
+            manufacturer, caption = _wmi_query('CPU', 'Manufacturer', 'Caption')
+        except OSError:
+            return os.environ.get('PROCESSOR_IDENTIFIER', _get_machine_win32())
+        else:
+            return f'{caption}, {manufacturer}'
+
+    def get_OpenVMS():
+        try:
+            import vms_lib
+        except ImportError:
+            pass
+        else:
+            csid, cpu_number = vms_lib.getsyi('SYI$_CPU', 0)
+            return 'Alpha' if cpu_number >= 128 else 'VAX'
+
+    def from_subprocess():
+        """
+        Fall back to `uname -p`
+        """
+        try:
+            import subprocess
+        except ImportError:
+            return None
+        try:
+            return subprocess.check_output(
+                ['uname', '-p'],
+                stderr=subprocess.DEVNULL,
+                text=True,
+                encoding="utf8",
+            ).strip()
+        except (OSError, subprocess.CalledProcessError):
+            pass
+
+
+def _unknown_as_blank(val):
+    return '' if val == 'unknown' else val
+
+
+### Portable uname() interface
+
+class uname_result(
+    collections.namedtuple(
+        "uname_result_base",
+        "system node release version machine")
+        ):
+    """
+    A uname_result that's largely compatible with a
+    simple namedtuple except that 'processor' is
+    resolved late and cached to avoid calling "uname"
+    except when needed.
+    """
+
+    _fields = ('system', 'node', 'release', 'version', 'machine', 'processor')
+
+    @functools.cached_property
+    def processor(self):
+        return _unknown_as_blank(_Processor.get())
+
+    def __iter__(self):
+        return itertools.chain(
+            super().__iter__(),
+            (self.processor,)
+        )
+
+    @classmethod
+    def _make(cls, iterable):
+        # override factory to affect length check
+        num_fields = len(cls._fields) - 1
+        result = cls.__new__(cls, *iterable)
+        if len(result) != num_fields + 1:
+            msg = f'Expected {num_fields} arguments, got {len(result)}'
+            raise TypeError(msg)
+        return result
+
+    def __getitem__(self, key):
+        return tuple(self)[key]
+
+    def __len__(self):
+        return len(tuple(iter(self)))
+
+    def __reduce__(self):
+        return uname_result, tuple(self)[:len(self._fields) - 1]
+
+
+_uname_cache = None
+
+
+def uname():
+
+    """ Fairly portable uname interface. Returns a tuple
+        of strings (system, node, release, version, machine, processor)
+        identifying the underlying platform.
+
+        Note that unlike the os.uname function this also returns
+        possible processor information as an additional tuple entry.
+
+        Entries which cannot be determined are set to ''.
+
+    """
+    global _uname_cache
+
+    if _uname_cache is not None:
+        return _uname_cache
+
+    # Get some infos from the builtin os.uname API...
+    try:
+        system, node, release, version, machine = infos = os.uname()
+    except AttributeError:
+        system = sys.platform
+        node = _node()
+        release = version = machine = ''
+        infos = ()
+
+    if not any(infos):
+        # uname is not available
+
+        # Try win32_ver() on win32 platforms
+        if system == 'win32':
+            release, version, csd, ptype = win32_ver()
+            machine = machine or _get_machine_win32()
+
+        # Try the 'ver' system command available on some
+        # platforms
+        if not (release and version):
+            system, release, version = _syscmd_ver(system)
+            # Normalize system to what win32_ver() normally returns
+            # (_syscmd_ver() tends to return the vendor name as well)
+            if system == 'Microsoft Windows':
+                system = 'Windows'
+            elif system == 'Microsoft' and release == 'Windows':
+                # Under Windows Vista and Windows Server 2008,
+                # Microsoft changed the output of the ver command. The
+                # release is no longer printed.  This causes the
+                # system and release to be misidentified.
+                system = 'Windows'
+                if '6.0' == version[:3]:
+                    release = 'Vista'
+                else:
+                    release = ''
+
+        # In case we still don't know anything useful, we'll try to
+        # help ourselves
+        if system in ('win32', 'win16'):
+            if not version:
+                if system == 'win32':
+                    version = '32bit'
+                else:
+                    version = '16bit'
+            system = 'Windows'
+
+        elif system[:4] == 'java':
+            release, vendor, vminfo, osinfo = java_ver()
+            system = 'Java'
+            version = ', '.join(vminfo)
+            if not version:
+                version = vendor
+
+    # System specific extensions
+    if system == 'OpenVMS':
+        # OpenVMS seems to have release and version mixed up
+        if not release or release == '0':
+            release = version
+            version = ''
+
+    #  normalize name
+    if system == 'Microsoft' and release == 'Windows':
+        system = 'Windows'
+        release = 'Vista'
+
+    vals = system, node, release, version, machine
+    # Replace 'unknown' values with the more portable ''
+    _uname_cache = uname_result(*map(_unknown_as_blank, vals))
+    return _uname_cache
+
+### Direct interfaces to some of the uname() return values
+
+def system():
+
+    """ Returns the system/OS name, e.g. 'Linux', 'Windows' or 'Java'.
+
+        An empty string is returned if the value cannot be determined.
+
+    """
+    return uname().system
+
+def node():
+
+    """ Returns the computer's network name (which may not be fully
+        qualified)
+
+        An empty string is returned if the value cannot be determined.
+
+    """
+    return uname().node
+
+def release():
+
+    """ Returns the system's release, e.g. '2.2.0' or 'NT'
+
+        An empty string is returned if the value cannot be determined.
+
+    """
+    return uname().release
+
+def version():
+
+    """ Returns the system's release version, e.g. '#3 on degas'
+
+        An empty string is returned if the value cannot be determined.
+
+    """
+    return uname().version
+
+def machine():
+
+    """ Returns the machine type, e.g. 'i386'
+
+        An empty string is returned if the value cannot be determined.
+
+    """
+    return uname().machine
+
+def processor():
+
+    """ Returns the (true) processor name, e.g. 'amdk6'
+
+        An empty string is returned if the value cannot be
+        determined. Note that many platforms do not provide this
+        information or simply return the same value as for machine(),
+        e.g.  NetBSD does this.
+
+    """
+    return uname().processor
+
+### Various APIs for extracting information from sys.version
+
+_sys_version_cache = {}
+
+def _sys_version(sys_version=None):
+
+    """ Returns a parsed version of Python's sys.version as tuple
+        (name, version, branch, revision, buildno, builddate, compiler)
+        referring to the Python implementation name, version, branch,
+        revision, build number, build date/time as string and the compiler
+        identification string.
+
+        Note that unlike the Python sys.version, the returned value
+        for the Python version will always include the patchlevel (it
+        defaults to '.0').
+
+        The function returns empty strings for tuple entries that
+        cannot be determined.
+
+        sys_version may be given to parse an alternative version
+        string, e.g. if the version was read from a different Python
+        interpreter.
+
+    """
+    # Get the Python version
+    if sys_version is None:
+        sys_version = sys.version
+
+    # Try the cache first
+    result = _sys_version_cache.get(sys_version, None)
+    if result is not None:
+        return result
+
+    sys_version_parser = re.compile(
+        r'([\w.+]+)\s*'  # "version<space>"
+        r'\(#?([^,]+)'  # "(#buildno"
+        r'(?:,\s*([\w ]*)'  # ", builddate"
+        r'(?:,\s*([\w :]*))?)?\)\s*'  # ", buildtime)<space>"
+        r'\[([^\]]+)\]?', re.ASCII)  # "[compiler]"
+
+    if sys.platform.startswith('java'):
+        # Jython
+        name = 'Jython'
+        match = sys_version_parser.match(sys_version)
+        if match is None:
+            raise ValueError(
+                'failed to parse Jython sys.version: %s' %
+                repr(sys_version))
+        version, buildno, builddate, buildtime, _ = match.groups()
+        if builddate is None:
+            builddate = ''
+        compiler = sys.platform
+
+    elif "PyPy" in sys_version:
+        # PyPy
+        pypy_sys_version_parser = re.compile(
+            r'([\w.+]+)\s*'
+            r'\(#?([^,]+),\s*([\w ]+),\s*([\w :]+)\)\s*'
+            r'\[PyPy [^\]]+\]?')
+
+        name = "PyPy"
+        match = pypy_sys_version_parser.match(sys_version)
+        if match is None:
+            raise ValueError("failed to parse PyPy sys.version: %s" %
+                             repr(sys_version))
+        version, buildno, builddate, buildtime = match.groups()
+        compiler = ""
+
+    else:
+        # CPython
+        match = sys_version_parser.match(sys_version)
+        if match is None:
+            raise ValueError(
+                'failed to parse CPython sys.version: %s' %
+                repr(sys_version))
+        version, buildno, builddate, buildtime, compiler = \
+              match.groups()
+        name = 'CPython'
+        if builddate is None:
+            builddate = ''
+        elif buildtime:
+            builddate = builddate + ' ' + buildtime
+
+    if hasattr(sys, '_git'):
+        _, branch, revision = sys._git
+    elif hasattr(sys, '_mercurial'):
+        _, branch, revision = sys._mercurial
+    else:
+        branch = ''
+        revision = ''
+
+    # Add the patchlevel version if missing
+    l = version.split('.')
+    if len(l) == 2:
+        l.append('0')
+        version = '.'.join(l)
+
+    # Build and cache the result
+    result = (name, version, branch, revision, buildno, builddate, compiler)
+    _sys_version_cache[sys_version] = result
+    return result
+
+def python_implementation():
+
+    """ Returns a string identifying the Python implementation.
+
+        Currently, the following implementations are identified:
+          'CPython' (C implementation of Python),
+          'Jython' (Java implementation of Python),
+          'PyPy' (Python implementation of Python).
+
+    """
+    return _sys_version()[0]
+
+def python_version():
+
+    """ Returns the Python version as string 'major.minor.patchlevel'
+
+        Note that unlike the Python sys.version, the returned value
+        will always include the patchlevel (it defaults to 0).
+
+    """
+    return _sys_version()[1]
+
+def python_version_tuple():
+
+    """ Returns the Python version as tuple (major, minor, patchlevel)
+        of strings.
+
+        Note that unlike the Python sys.version, the returned value
+        will always include the patchlevel (it defaults to 0).
+
+    """
+    return tuple(_sys_version()[1].split('.'))
+
+def python_branch():
+
+    """ Returns a string identifying the Python implementation
+        branch.
+
+        For CPython this is the SCM branch from which the
+        Python binary was built.
+
+        If not available, an empty string is returned.
+
+    """
+
+    return _sys_version()[2]
+
+def python_revision():
+
+    """ Returns a string identifying the Python implementation
+        revision.
+
+        For CPython this is the SCM revision from which the
+        Python binary was built.
+
+        If not available, an empty string is returned.
+
+    """
+    return _sys_version()[3]
+
+def python_build():
+
+    """ Returns a tuple (buildno, builddate) stating the Python
+        build number and date as strings.
+
+    """
+    return _sys_version()[4:6]
+
+def python_compiler():
+
+    """ Returns a string identifying the compiler used for compiling
+        Python.
+
+    """
+    return _sys_version()[6]
+
+### The Opus Magnum of platform strings :-)
+
+_platform_cache = {}
+
+def platform(aliased=False, terse=False):
+
+    """ Returns a single string identifying the underlying platform
+        with as much useful information as possible (but no more :).
+
+        The output is intended to be human readable rather than
+        machine parseable. It may look different on different
+        platforms and this is intended.
+
+        If "aliased" is true, the function will use aliases for
+        various platforms that report system names which differ from
+        their common names, e.g. SunOS will be reported as
+        Solaris. The system_alias() function is used to implement
+        this.
+
+        Setting terse to true causes the function to return only the
+        absolute minimum information needed to identify the platform.
+
+    """
+    result = _platform_cache.get((aliased, terse), None)
+    if result is not None:
+        return result
+
+    # Get uname information and then apply platform specific cosmetics
+    # to it...
+    system, node, release, version, machine, processor = uname()
+    if machine == processor:
+        processor = ''
+    if aliased:
+        system, release, version = system_alias(system, release, version)
+
+    if system == 'Darwin':
+        # macOS (darwin kernel)
+        macos_release = mac_ver()[0]
+        if macos_release:
+            system = 'macOS'
+            release = macos_release
+
+    if system == 'Windows':
+        # MS platforms
+        rel, vers, csd, ptype = win32_ver(version)
+        if terse:
+            platform = _platform(system, release)
+        else:
+            platform = _platform(system, release, version, csd)
+
+    elif system == 'Linux':
+        # check for libc vs. glibc
+        libcname, libcversion = libc_ver()
+        platform = _platform(system, release, machine, processor,
+                             'with',
+                             libcname+libcversion)
+    elif system == 'Java':
+        # Java platforms
+        r, v, vminfo, (os_name, os_version, os_arch) = java_ver()
+        if terse or not os_name:
+            platform = _platform(system, release, version)
+        else:
+            platform = _platform(system, release, version,
+                                 'on',
+                                 os_name, os_version, os_arch)
+
+    else:
+        # Generic handler
+        if terse:
+            platform = _platform(system, release)
+        else:
+            bits, linkage = architecture(sys.executable)
+            platform = _platform(system, release, machine,
+                                 processor, bits, linkage)
+
+    _platform_cache[(aliased, terse)] = platform
+    return platform
+
+### freedesktop.org os-release standard
+# https://www.freedesktop.org/software/systemd/man/os-release.html
+
+# /etc takes precedence over /usr/lib
+_os_release_candidates = ("/etc/os-release", "/usr/lib/os-release")
+_os_release_cache = None
+
+
+def _parse_os_release(lines):
+    # These fields are mandatory fields with well-known defaults
+    # in practice all Linux distributions override NAME, ID, and PRETTY_NAME.
+    info = {
+        "NAME": "Linux",
+        "ID": "linux",
+        "PRETTY_NAME": "Linux",
+    }
+
+    # NAME=value with optional quotes (' or "). The regular expression is less
+    # strict than shell lexer, but that's ok.
+    os_release_line = re.compile(
+        "^(?P<name>[a-zA-Z0-9_]+)=(?P<quote>[\"\']?)(?P<value>.*)(?P=quote)$"
+    )
+    # unescape five special characters mentioned in the standard
+    os_release_unescape = re.compile(r"\\([\\\$\"\'`])")
+
+    for line in lines:
+        mo = os_release_line.match(line)
+        if mo is not None:
+            info[mo.group('name')] = os_release_unescape.sub(
+                r"\1", mo.group('value')
+            )
+
+    return info
+
+
+def freedesktop_os_release():
+    """Return operation system identification from freedesktop.org os-release
+    """
+    global _os_release_cache
+
+    if _os_release_cache is None:
+        errno = None
+        for candidate in _os_release_candidates:
+            try:
+                with open(candidate, encoding="utf-8") as f:
+                    _os_release_cache = _parse_os_release(f)
+                break
+            except OSError as e:
+                errno = e.errno
+        else:
+            raise OSError(
+                errno,
+                f"Unable to read files {', '.join(_os_release_candidates)}"
+            )
+
+    return _os_release_cache.copy()
+
+
+### Command line interface
+
+if __name__ == '__main__':
+    # Default is to print the aliased verbose platform string
+    terse = ('terse' in sys.argv or '--terse' in sys.argv)
+    aliased = (not 'nonaliased' in sys.argv and not '--nonaliased' in sys.argv)
+    print(platform(aliased, terse))
+    sys.exit(0)