Para ilustrar a sequência do que fiz aqui usando um live-iso do Ubuntu 14.04.2 e que resultou sucesso, google calendar instalado e funcionando:
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ubuntu@ubuntu:~$ sudo apt-get install calendar-indicator
Reading package lists... Done
Building dependency tree
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:
The following packages have unmet dependencies:
calendar-indicator : Depends: python3-dateutil but it is not installable
E: Unable to correct problems, you have held broken packages.
ubuntu@ubuntu:~$
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ubuntu@ubuntu:~$ sudo apt-get install python3-dateutil
Reading package lists... Done
Building dependency tree
Reading state information... Done
Package python3-dateutil 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 'python3-dateutil' has no installation candidate
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ubuntu@ubuntu:~$ sudo apt-get install python-dateutil
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following NEW packages will be installed:
python-dateutil
0 upgraded, 1 newly installed, 0 to remove and 235 not upgraded.
Need to get 48.9 kB of archives.
After this operation, 221 kB of additional disk space will be used.
Get:1 http://archive.ubuntu.com/ubuntu/ trusty/main python-dateutil all 1.5+dfsg-1ubuntu1 [48.9 kB]
Fetched 48.9 kB in 0s (64.9 kB/s)
Selecting previously unselected package python-dateutil.
(Reading database ... 174342 files and directories currently installed.)
Preparing to unpack .../python-dateutil_1.5+dfsg-1ubuntu1_all.deb ...
Unpacking python-dateutil (1.5+dfsg-1ubuntu1) ...
Setting up python-dateutil (1.5+dfsg-1ubuntu1) ...
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ubuntu@ubuntu:~$ sudo apt-get install calendar-indicator
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following extra packages will be installed:
python3-dateutil
The following NEW packages will be installed:
calendar-indicator python3-dateutil
0 upgraded, 2 newly installed, 0 to remove and 235 not upgraded.
Need to get 317 kB of archives.
After this operation, 3,711 kB of additional disk space will be used.
Do you want to continue? [Y/n] y
Get:1 http://archive.ubuntu.com/ubuntu/ trusty/universe python3-dateutil all 2.0+dfsg1-1 [49.3 kB]
Get:2 http://ppa.launchpad.net/atareao/atareao/ubuntu/ trusty/main calendar-indicator all 0.3.1-0extras14.04.3 [268 kB]
Fetched 317 kB in 2s (150 kB/s)
Selecting previously unselected package python3-dateutil.
(Reading database ... 174365 files and directories currently installed.)
Preparing to unpack .../python3-dateutil_2.0+dfsg1-1_all.deb ...
Unpacking python3-dateutil (2.0+dfsg1-1) ...
Selecting previously unselected package calendar-indicator.
Preparing to unpack .../calendar-indicator_0.3.1-0extras14.04.3_all.deb ...
Unpacking calendar-indicator (0.3.1-0extras14.04.3) ...
Processing triggers for gnome-menus (3.10.1-0ubuntu2) ...
Processing triggers for desktop-file-utils (0.22-1ubuntu1) ...
Processing triggers for bamfdaemon (0.5.1+14.04.20140409-0ubuntu1) ...
Rebuilding /usr/share/applications/bamf-2.index...
Processing triggers for mime-support (3.54ubuntu1.1) ...
Setting up python3-dateutil (2.0+dfsg1-1) ...
Setting up calendar-indicator (0.3.1-0extras14.04.3) ...
ubuntu@ubuntu:~$
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