Installation of the unity stock ticker lens failed

Question

The following packages have unmet dependencies:

unity-stock-ticker-lens : Depends: python-unity-singlet (>= 0.3) but it is not going to be installed
E: Unable to correct problems, you have held broken packages.

Answer 1

Open your terminal and try the following:

sudo apt-get -f install

The above will try to resolve the missing dependencies and broken packages

Answer 2

Go to Ubuntu Software center search for python-unity-singlet. In front of package name there is the version, select version 0.3 (quantal-backports) and install.
Proceed with Ticker lens installation, it should install now.