I'm having an issue with update-manager. Last night, my computer restart suddenly during the update process. Now it won't open and it keep appearing on the notifier with a message warning that an error occurred. The error is the same that is displayed when I try to open it on the terminal:

Error in sitecustomize; set PYTHONVERBOSE for traceback:
EOFError: EOF read where not expected
Traceback (most recent call last):
 File "/usr/bin/update-manager", line 26, in <module>
 from __future__ import print_function
EOFError: EOF read where not expected

I've already seen some questions here, but most of them are related to problems with ppas and the source.list file. This seems to be a bug on update-manager itself. I've already tried to remove it and install again, but the problem persists. I also noted another bug: my source-center doesn't open too. The message for it is similar to the other one:

Error in sitecustomize; set PYTHONVERBOSE for traceback:
EOFError: EOF read where not expected
Traceback (most recent call last):
  File "/usr/lib/command-not-found", line 5, in <module>
    from __future__ import absolute_import, print_function
EOFError: EOF read where not expected

For now I'm using apt-get update && upgrade for updating and the Synaptic for the source management. But I really would like to fix this stuff. Anyone can help?

I'm with Ubuntu 12.10, Gnome-remix, 64-bits.