Install Updates could not successfully download and install available updates.

[atpersian]

i edit it it get error as bellow:
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on sudo apt-get remove --purge gconf2
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python3
update-notifier-common
python3-update-manager
ubiquity-frontend-debconf
netplan.io
ubuntu-release-upgrader-core
software-properties-gtk
nplan
python3-software-properties
gnome-menus
ubiquity
ubiquity-frontend-gtk
python3-distupgrade
software-properties-common
ufw
update-manager-core
python3-apt
E: Sub-process /usr/bin/dpkg returned an error code (1)

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on  sudo apt-get install gconf2:
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Reading package lists... Done
Building dependency tree     
Reading state information... Done
Package gconf2 is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source

E: Package 'gconf2' has no installation candidate