Comment 7 for bug 834196

Hi,
If you don't know how to write python code, it's probably best not to try modifying the code, as you will need to get the indents correct etc.
The issue has been fixed and will be available in the next software-center update, so my strong advice is to wait for that.

However if you are intent on fixing it before then, it's best to get the entire updated softwarepane.py file from here:
http://bazaar.launchpad.net/~kiwinote/software-center/tweaks/download/kiwinote%40gmail.com-20110826110015-fobea07so04vh5kv/softwarepane.py-20110705095105-hkqkaog02375crmg-28/softwarepane.py

Then copy it into your current installation (i.e. /usr/share/software-center/softwarecenter/ui/gtk3/panes/) using sudo. (I would make a backup copy of your existing softwarepane.py file first)
Note, this could break your installation temporarily and may also have other unintended effects so attempt it at your own risk.

cheers
Aaron