Ubuntu 12.10, can’t seem to get add-apt-repository

Ubuntu

I am attempting to add some external packages to Ubuntu 12.10 from a PPA. To do so, I need to use add-apt-repository. Easy enough – add-apt-repository: command not found in Ubuntu 10.04 tells me to install python-software-properties. I have done that – here's proof that it is already there:

user@hostname:~$ sudo apt-get install python-software-properties
Reading package lists... Done
Building dependency tree
Reading state information... Done
python-software-properties is already the newest version.
0 upgraded, 0 newly installed, 0 to remove and 58 not upgraded.

Yet, I still don't have add-apt-repository:

user@hostname:~$ sudo add-apt-repository
sudo: add-apt-repository: command not found
user@hostname:~$ add-apt-repository
The program 'add-apt-repository' can be found in the following packages:
 * python-software-properties
 * software-properties-common
Try: sudo apt-get install <selected package>

What (obvious?) thing am I missing?

Best Answer

I found it almost immediately after asking the question. I need both packages - I added software-properties-common and I am good. Although that was not at all obvious to me from the error.