8000 bpo-28468: Add platform.freedesktop_os_release() (GH-23492) · python/cpython@5c73afc · GitHub
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bpo-28468: Add platform.freedesktop_os_release() (GH-23492)
Add platform.freedesktop_os_release() function to parse freedesktop.org os-release files. Signed-off-by: Christian Heimes <christian@python.org> Co-authored-by: Victor Stinner <vstinner@python.org>
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‎Doc/library/platform.rst

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@@ -253,3 +253,41 @@ Unix Platforms
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using :program:`gcc`.
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The file is read and scanned in chunks of *chunksize* bytes.
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Linux Platforms
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---------------
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.. function:: freedesktop_os_release()
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Get operating system identification from ``os-release`` file and return
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it as a dict. The ``os-release`` file is a `freedesktop.org standard
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<https://www.freedesktop.org/software/systemd/man/os-release.html>`_ and
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is available in most Linux distributions. A noticeable exception is
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Android and Android-based distributions.
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Raises :exc:`OSError` or subclass when neither ``/etc/os-release`` nor
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``/usr/lib/os-release`` can be read.
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On success, the function returns a dictionary where keys and values are
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strings. Values have their special characters like ``"`` and ``$``
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unquoted. The fields ``NAME``, ``ID``, and ``PRETTY_NAME`` are always
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defined according to the standard. All other fields are optional. Vendors
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may include additional fields.
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Note that fields like ``NAME``, ``VERSION``, and ``VARIANT`` are strings
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suitable for presentation to users. Programs should use fields like
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``ID``, ``ID_LIKE``, ``VERSION_ID``, or ``VARIANT_ID`` to identify
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Linux distributions.
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Example::
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def get_like_distro():
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info = platform.freedesktop_os_release()
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ids = [info["ID"]]
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if "ID_LIKE" in info:
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# ids are space separated and ordered by precedence
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ids.extend(info["ID_LIKE"].split())
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return ids
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.. versionadded:: 3.10

‎Doc/whatsnew/3.10.rst

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<pathlib.PurePath.parents>`.
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(Contributed by Yaroslav Pankovych in :issue:`21041`)
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platform
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--------
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Added :func:`platform.freedesktop_os_release()` to retrieve operation system
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identification from `freedesktop.org os-release
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<https://www.freedesktop.org/software/systemd/man/os-release.html>`_ standard file.
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(Contributed by Christian Heimes in :issue:`28468`)
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py_compile
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----------
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‎Lib/platform.py

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@@ -1230,6 +1230,63 @@ def platform(aliased=0, terse=0):
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_platform_cache[(aliased, terse)] = platform
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return platform
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### freedesktop.org os-release standard
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# https://www.freedesktop.org/software/systemd/man/os-release.html
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# NAME=value with optional quotes (' or "). The regular expression is less
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# strict than shell lexer, but that's ok.
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_os_release_line = re.compile(
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"^(?P<name>[a-zA-Z0-9_]+)=(?P<quote>[\"\']?)(?P<value>.*)(?P=quote)$"
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)
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# unescape five special characters mentioned in the standard
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_os_release_unescape = re.compile(r"\\([\\\$\"\'`])")
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# /etc takes precedence over /usr/lib
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_os_release_candidates = ("/etc/os-release", "/usr/lib/os-relesase")
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_os_release_cache = None
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def _parse_os_release(lines):
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# These fields are mandatory fields with well-known defaults
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# in pratice all Linux distributions override NAME, ID, and PRETTY_NAME.
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info = {
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"NAME": "Linux",
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"ID": "linux",
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"PRETTY_NAME": "Linux",
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}
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for line in lines:
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mo = _os_release_line.match(line)
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if mo is not None:
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info[mo.group('name')] = _os_release_unescape.sub(
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r"\1", mo.group('value')
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)
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return info
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def freedesktop_os_release():
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"""Return operation system identification from freedesktop.org os-release
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"""
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global _os_release_cache
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if _os_release_cache is None:
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errno = None
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for candidate in _os_release_candidates:
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try:
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with open(candidate, encoding="utf-8") as f:
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_os_release_cache = _parse_os_release(f)
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break
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except OSError as e:
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errno = e.errno
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else:
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raise OSError(
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errno,
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f"Unable to read files {', '.join(_os_release_candidates)}"
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)
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return _os_release_cache.copy()
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### Command line interface
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if __name__ == '__main__':

‎Lib/test/test_platform.py

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from test import support
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from test.support import os_helper
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FEDORA_OS_RELEASE = """\
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NAME=Fedora
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VERSION="32 (Thirty Two)"
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ID=fedora
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VERSION_ID=32
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VERSION_CODENAME=""
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PLATFORM_ID="platform:f32"
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PRETTY_NAME="Fedora 32 (Thirty Two)"
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ANSI_COLOR="0;34"
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LOGO=fedora-logo-icon
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CPE_NAME="cpe:/o:fedoraproject:fedora:32"
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HOME_URL="https://fedoraproject.org/"
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DOCUMENTATION_URL="https://docs.fedoraproject.org/en-US/fedora/f32/system-administrators-guide/"
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SUPPORT_URL="https://fedoraproject.org/wiki/Communicating_and_getting_help"
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BUG_REPORT_URL="https://bugzilla.redhat.com/"
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REDHAT_BUGZILLA_PRODUCT="Fedora"
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REDHAT_BUGZILLA_PRODUCT_VERSION=32
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REDHAT_SUPPORT_PRODUCT="Fedora"
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REDHAT_SUPPORT_PRODUCT_VERSION=32
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PRIVACY_POLICY_URL="https://fedoraproject.org/wiki/Legal:PrivacyPolicy"
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"""
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UBUNTU_OS_RELEASE = """\
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NAME="Ubuntu"
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VERSION="20.04.1 LTS (Focal Fossa)"
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ID=ubuntu
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ID_LIKE=debian
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PRETTY_NAME="Ubuntu 20.04.1 LTS"
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VERSION_ID="20.04"
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HOME_URL="https://www.ubuntu.com/"
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SUPPORT_URL="https://help.ubuntu.com/"
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BUG_REPORT_URL="https://bugs.launchpad.net/ubuntu/"
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PRIVACY_POLICY_URL="https://www.ubuntu.com/legal/terms-and-policies/privacy-policy"
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VERSION_CODENAME=focal
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UBUNTU_CODENAME=focal
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"""
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TEST_OS_RELEASE = r"""
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# test data
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ID_LIKE="egg spam viking"
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EMPTY=
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# comments and empty lines are ignored
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SINGLE_QUOTE='single'
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EMPTY_SINGLE=''
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DOUBLE_QUOTE="double"
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EMPTY_DOUBLE 10000 =""
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QUOTES="double\'s"
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SPECIALS="\$\`\\\'\""
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# invalid lines
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=invalid
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=
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INVALID
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IN-VALID=value
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IN VALID=value
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"""
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class PlatformTest(unittest.TestCase):
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def clear_caches(self):
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platform._platform_cache.clear()
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platform._sys_version_cache.clear()
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platform._uname_cache = None
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platform._os_release_cache = None
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def test_architecture(self):
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res = platform.architecture()
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self.assertEqual(platform.platform(terse=1), expected_terse)
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self.assertEqual(platform.platform(), expected)
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def test_freedesktop_os_release(self):
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self.addCleanup(self.clear_caches)
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self.clear_caches()
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if any(os.path.isfile(fn) for fn in platform._os_release_candidates):
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info = platform.freedesktop_os_release()
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self.assertIn("NAME", info)
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self.assertIn("ID", info)
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info["CPYTHON_TEST"] = "test"
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self.assertNotIn(
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"CPYTHON_TEST",
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platform.freedesktop_os_release()
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)
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else:
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with self.assertRaises(OSError):
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platform.freedesktop_os_release()
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def test_parse_os_release(self):
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info = platform._parse_os_release(FEDORA_OS_RELEASE.splitlines())
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self.assertEqual(info["NAME"], "Fedora")
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self.assertEqual(info["ID"], "fedora")
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self.assertNotIn("ID_LIKE", info)
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self.assertEqual(info["VERSION_CODENAME"], "")
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info = platform._parse_os_release(UBUNTU_OS_RELEASE.splitlines())
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self.assertEqual(info["NAME"], "Ubuntu")
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self.assertEqual(info["ID"], "ubuntu")
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self.assertEqual(info["ID_LIKE"], "debian")
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self.assertEqual(info["VERSION_CODENAME"], "focal")
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info = platform._parse_os_release(TEST_OS_RELEASE.splitlines())
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expected = {
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"ID": "linux",
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"NAME": "Linux",
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"PRETTY_NAME": "Linux",
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"ID_LIKE": "egg spam viking",
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"EMPTY": "",
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"DOUBLE_QUOTE": "double",
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"EMPTY_DOUBLE": "",
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"SINGLE_QUOTE": "single",
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"EMPTY_SINGLE": "",
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"QUOTES": "double's",
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"SPECIALS": "$`\\'\"",
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}
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self.assertEqual(info, expected)
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self.assertEqual(len(info["SPECIALS"]), 5)
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if __name__ == '__main__':
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unittest.main()

‎Misc/NEWS.d/next/Library/2020-11-24-13-18-05.bpo-28468.8Gh2d4.rst

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Add :func:`platform.freedesktop_os_release` function to parse freedesktop.org
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``os-release`` files.

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