Drop Python < 3.10 support

Python 3.10 is the default in Jammy, while Debian Bookworm has 3.11

README.md

@@ -24,6 +24,15 @@ Please see https://wiki.ubuntu.com/Apport for more details and further links.
 The files in [doc/](./doc/) document particular details such as package hooks,
 crash database configuration, or the internal data format.
 
+Platform requirements
+----------------
+
+The absolute minimum requirement for your distribution are Python 3.10 or
+above. Depending on which features you want enabled, various Python packages
+also need to be available.
+
+TODO: document the Python dependencies
+
 Temporarily enabling apport
 ===========================
 

apport/packaging.py

@@ -13,49 +13,7 @@
 import subprocess
 import sys
 import typing
-
-try:
-    from platform import freedesktop_os_release
-except ImportError:  # Python < 3.10
-
-    def _parse_os_release(*os_release_files: str) -> typing.Dict[str, str]:
-        """Parse os-release and return a parameter dictionary.
-
-        This function will behave identical to
-        platform.freedesktop_os_release() from Python >= 3.10, if
-        called with ("/etc/os-release", "/usr/lib/os-release").
-
-        See http://www.freedesktop.org/software/systemd/man/os-release.html
-        for specification of the file format.
-        """
-        # These fields are mandatory fields with well-known defaults
-        # in practice all Linux distributions override NAME, ID, and
-        # PRETTY_NAME.
-        ret = {"NAME": "Linux", "ID": "linux", "PRETTY_NAME": "Linux"}
-
-        errno = None
-        for filename in os_release_files:
-            try:
-                with open(filename, encoding="utf-8") as release_file:
-                    regex = re.compile("^([\\w]+)=(?:'|\")?(.*?)(?:'|\")?$")
-                    for line in release_file:
-                        match = regex.match(line.strip())
-                        if match:
-                            # Shell special characters ("$", quotes, backslash,
-                            # backtick) are escaped with backslashes
-                            ret[match.group(1)] = re.sub(
-                                r'\\([$"\'\\`])', r"\1", match.group(2)
-                            )
-                break
-            except OSError as error:
-                errno = error.errno
-        else:
-            raise OSError(errno, f"Unable to read files {', '.join(os_release_files)}")
-
-        return ret
-
-    def freedesktop_os_release() -> typing.Dict[str, str]:
-        return _parse_os_release("/etc/os-release", "/usr/lib/os-release")
+from platform import freedesktop_os_release
 
 
 class PackageInfo: