apt - Install pyqt4 . Unable to locate package - Ask Ubuntu

in order install electrum bitcoin wallet, need install pyqt4. when run command sudo apt-get install python-qt4 error "unable locate package". how can solve this?

i'm on ubuntu 16.04.

thanks lot help

first try this:

sudo apt-get clean sudo apt-get update sudo apt-get upgrade  

then this:

sudo add-apt-repository main sudo add-apt-repository universe sudo add-apt-repository restricted sudo add-apt-repository multiverse 

then before try installing package again, suggest looking sources list:

nano /etc/apt/sources.list 

go online , @ ubuntu default source list supposed , compare yours. if fine, go on , install package. if still error, reply back.