venv) aruns plivo $ sudo apt-get install postgresql postgresql-contrib libpq-dev python-dev
Reading package lists... Done
Building dependency tree       
Reading state information... Done
python-dev is already the newest version.
postgresql is already the newest version.
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:
 libpq-dev : Depends: libpq5 (= 9.3.4-1) but 9.3.14-0ubuntu0.14.04 is to be installed
 postgresql-contrib : Depends: postgresql-contrib-9.3 but it is not going to be installed
E: Unable to correct problems, you have held broken packages.