Let's not focus on that. It is misleading.
The software-properties-gtk app is the Software & Updates app.
The Update-manager is processed through the .py script. These are necessarily going to run, so observing that they run is not indicative of anything other than that they run.
The .py script itself does not contain the error because if it did; then that error would show on all systems running it.
The error is far more likely to occur due to a difference between the logged updates and the communicated updates via the server.
journalctl -b -p err
-- Logs begin at Mon 2023-06-05 07:55:17 -03, end at Wed 2023-06-07 16:22:56 -03. --
jun 07 16:06:26 jeiel-To-be-filled-by-O-E-M systemd[1]: Failed to start Show Plymouth Boot Screen.
jun 07 16:06:28 jeiel-To-be-filled-by-O-E-M /usr/sbin/irqbalance[524]: libcap-ng used by "/usr/sbin/irqbalance" failed dropping bounding set due to not having CAP_SETPCAP in capng_apply
jun 07 16:06:34 jeiel-To-be-filled-by-O-E-M lightdm[820]: gkr-pam: couldn't unlock the login keyring.
jun 07 16:06:35 jeiel-To-be-filled-by-O-E-M bluetoothd[1097]: Can't load plugin /usr/lib/x86_64-linux-gnu/bluetooth/plugins/sixaxis.so: /usr/lib/x86_64-linux-gnu/bluetooth/plugins/sixaxis.so: undefined symbol: btd_device_is_trusted
jun 07 16:06:35 jeiel-To-be-filled-by-O-E-M systemd[1114]: Excess arguments.
jun 07 16:06:58 jeiel-To-be-filled-by-O-E-M lightdm[1347]: gkr-pam: unable to locate daemon control file
jun 07 16:06:58 jeiel-To-be-filled-by-O-E-M pulseaudio[1001]: Error opening PCM device hdmi:0: Arquivo ou diretório inexistente
journalctl -b -p warning
-- Logs begin at Mon 2023-06-05 07:55:17 -03, end at Wed 2023-06-07 16:23:15 -03. --
jun 07 16:06:25 jeiel-To-be-filled-by-O-E-M kernel: ACPI BIOS Warning (bug): 32/64X length mismatch in FADT/Gpe0Block: 128/32 (20210730/tbfadt-564)
jun 07 16:06:25 jeiel-To-be-filled-by-O-E-M kernel: ACPI: NMI not connected to LINT 1!
jun 07 16:06:25 jeiel-To-be-filled-by-O-E-M kernel: ACPI: NMI not connected to LINT 1!
jun 07 16:06:25 jeiel-To-be-filled-by-O-E-M kernel: ENERGY_PERF_BIAS: Set to 'normal', was 'performance'
jun 07 16:06:25 jeiel-To-be-filled-by-O-E-M kernel: hpet: number irqs doesn't agree with number of timers
jun 07 16:06:25 jeiel-To-be-filled-by-O-E-M kernel: device-mapper: core: CONFIG_IMA_DISABLE_HTABLE is disabled. Duplicate IMA measurements will not be recorded in the IMA log.
jun 07 16:06:25 jeiel-To-be-filled-by-O-E-M kernel: platform eisa.0: EISA: Cannot allocate resource for mainboard
jun 07 16:06:25 jeiel-To-be-filled-by-O-E-M kernel: platform eisa.0: Cannot allocate resource for EISA slot 1
jun 07 16:06:25 jeiel-To-be-filled-by-O-E-M kernel: platform eisa.0: Cannot allocate resource for EISA slot 2
jun 07 16:06:25 jeiel-To-be-filled-by-O-E-M kernel: platform eisa.0: Cannot allocate resource for EISA slot 3
jun 07 16:06:25 jeiel-To-be-filled-by-O-E-M kernel: platform eisa.0: Cannot allocate resource for EISA slot 4
jun 07 16:06:25 jeiel-To-be-filled-by-O-E-M kernel: platform eisa.0: Cannot allocate resource for EISA slot 5
jun 07 16:06:25 jeiel-To-be-filled-by-O-E-M kernel: platform eisa.0: Cannot allocate resource for EISA slot 6
jun 07 16:06:25 jeiel-To-be-filled-by-O-E-M kernel: platform eisa.0: Cannot allocate resource for EISA slot 7
jun 07 16:06:25 jeiel-To-be-filled-by-O-E-M kernel: platform eisa.0: Cannot allocate resource for EISA slot 8
jun 07 16:06:26 jeiel-To-be-filled-by-O-E-M systemd[1]: plymouth-start.service: Main process exited, code=killed, status=6/ABRT
jun 07 16:06:26 jeiel-To-be-filled-by-O-E-M systemd[1]: plymouth-start.service: Failed with result 'signal'.
jun 07 16:06:26 jeiel-To-be-filled-by-O-E-M systemd[1]: Failed to start Show Plymouth Boot Screen.
jun 07 16:06:26 jeiel-To-be-filled-by-O-E-M (udev-worker)[322]: sda: Process '/usr/bin/unshare -m /usr/bin/snap auto-import --mount=/dev/sda' failed with exit code 1.
jun 07 16:06:26 jeiel-To-be-filled-by-O-E-M (udev-worker)[312]: sda2: Process '/usr/bin/unshare -m /usr/bin/snap auto-import --mount=/dev/sda2' failed with exit code 1.
jun 07 16:06:26 jeiel-To-be-filled-by-O-E-M (udev-worker)[303]: sda5: Process '/usr/bin/unshare -m /usr/bin/snap auto-import --mount=/dev/sda5' failed with exit code 1.
jun 07 16:06:26 jeiel-To-be-filled-by-O-E-M (udev-worker)[322]: sda1: Process '/usr/bin/unshare -m /usr/bin/snap auto-import --mount=/dev/sda1' failed with exit code 1.
jun 07 16:06:26 jeiel-To-be-filled-by-O-E-M kernel: atomisp_gmin_platform: module is from the staging directory, the quality is unknown, you have been warned.
jun 07 16:06:26 jeiel-To-be-filled-by-O-E-M kernel: atomisp_lm3554: module is from the staging directory, the quality is unknown, you have been warned.
jun 07 16:06:27 jeiel-To-be-filled-by-O-E-M kernel: mei_txe 0000:00:1a.0: can't derive routing for PCI INT A
jun 07 16:06:27 jeiel-To-be-filled-by-O-E-M kernel: mei_txe 0000:00:1a.0: PCI INT A: not connected
jun 07 16:06:27 jeiel-To-be-filled-by-O-E-M kernel: at24 0-0050: supply vcc not found, using dummy regulator
jun 07 16:06:28 jeiel-To-be-filled-by-O-E-M /usr/sbin/irqbalance[524]: libcap-ng used by "/usr/sbin/irqbalance" failed dropping bounding set due to not having CAP_SETPCAP in capng_apply
jun 07 16:06:28 jeiel-To-be-filled-by-O-E-M thermald[578]: NO RAPL sysfs present
jun 07 16:06:28 jeiel-To-be-filled-by-O-E-M thermald[578]: NO RAPL sysfs present
jun 07 16:06:28 jeiel-To-be-filled-by-O-E-M udisksd[581]: failed to load bd_crypto_bitlk_open: /lib/x86_64-linux-gnu/libbd_crypto.so.2: undefined symbol: bd_crypto_bitlk_open
jun 07 16:06:28 jeiel-To-be-filled-by-O-E-M udisksd[581]: failed to load bd_crypto_bitlk_close: /lib/x86_64-linux-gnu/libbd_crypto.so.2: undefined symbol: bd_crypto_bitlk_close
jun 07 16:06:28 jeiel-To-be-filled-by-O-E-M udisksd[581]: failed to load module mdraid: libbd_mdraid.so.2: cannot open shared object file: No such file or directory
jun 07 16:06:29 jeiel-To-be-filled-by-O-E-M udisksd[581]: Failed to load the 'mdraid' libblockdev plugin
jun 07 16:06:30 jeiel-To-be-filled-by-O-E-M NetworkManager[515]: <warn> [1686164790.5930] ifupdown: interfaces file /etc/network/interfaces doesn't exist
jun 07 16:06:30 jeiel-To-be-filled-by-O-E-M blueman-mechani[508]: gtk_icon_theme_get_for_screen: assertion 'GDK_IS_SCREEN (screen)' failed
jun 07 16:06:30 jeiel-To-be-filled-by-O-E-M NetworkManager[515]: <warn> [1686164790.9027] Error: failed to open /run/network/ifstate
jun 07 16:06:33 jeiel-To-be-filled-by-O-E-M kernel: kauditd_printk_skb: 34 callbacks suppressed
jun 07 16:06:33 jeiel-To-be-filled-by-O-E-M systemd[1]: kerneloops.service: Found left-over process 912 (kerneloops) in control group while starting unit. Ignoring.
jun 07 16:06:33 jeiel-To-be-filled-by-O-E-M systemd[1]: This usually indicates unclean termination of a previous run, or service implementation deficiencies.
jun 07 16:06:33 jeiel-To-be-filled-by-O-E-M kernel: vboxdrv: loading out-of-tree module taints kernel.
jun 07 16:06:33 jeiel-To-be-filled-by-O-E-M kernel: VBoxNetFlt: Successfully started.
jun 07 16:06:34 jeiel-To-be-filled-by-O-E-M kernel: VBoxNetAdp: Successfully started.
jun 07 16:06:34 jeiel-To-be-filled-by-O-E-M lightdm[820]: gkr-pam: couldn't unlock the login keyring.
jun 07 16:06:35 jeiel-To-be-filled-by-O-E-M bluetoothd[1097]: Can't load plugin /usr/lib/x86_64-linux-gnu/bluetooth/plugins/sixaxis.so: /usr/lib/x86_64-linux-gnu/bluetooth/plugins/sixaxis.so: undefined symbol: btd_device_is_trusted
jun 07 16:06:35 jeiel-To-be-filled-by-O-E-M systemd[1114]: Excess arguments.
jun 07 16:06:58 jeiel-To-be-filled-by-O-E-M lightdm[1347]: gkr-pam: unable to locate daemon control file
jun 07 16:06:58 jeiel-To-be-filled-by-O-E-M pulseaudio[1001]: Error opening PCM device hdmi:0: Arquivo ou diretório inexistente
jun 07 16:07:02 jeiel-To-be-filled-by-O-E-M gnome-keyring-daemon[1663]: discover_other_daemon: 1
jun 07 16:07:10 jeiel-To-be-filled-by-O-E-M blueman-mechani[1922]: gtk_icon_theme_get_for_screen: assertion 'GDK_IS_SCREEN (screen)' failed
jun 07 16:07:36 jeiel-To-be-filled-by-O-E-M gnome-keyring-daemon[1380]: asked to register item /org/freedesktop/secrets/collection/login/1, but it's already registered
jun 07 16:07:36 jeiel-To-be-filled-by-O-E-M gnome-keyring-d[1380]: asked to register item /org/freedesktop/secrets/collection/login/1, but it's already registered
jun 07 16:07:53 jeiel-To-be-filled-by-O-E-M gnome-keyring-daemon[1380]: asked to register item /org/freedesktop/secrets/collection/login/1, but it's already registered
jun 07 16:07:53 jeiel-To-be-filled-by-O-E-M gnome-keyring-d[1380]: asked to register item /org/freedesktop/secrets/collection/login/1, but it's already registered
Miscellaneous warnings and issues. There are many and I don't know how to "read" like that.
Improved some lines that were broken diagonally. Broken lines are horizontally broken down to vertical. I'm giving up on the problem. I will continue like this until the system crashes or I cause this. Then I format it with pedrive.