Set them in /etc/environment the http_proxy and https_proxy or if is not possible edit your ~/.bashrc as follows:

PROXYUSER="proxy-user-here"
PROXYPASSWORD="proxy-password-here"
PROXYHOST="158.169.131.13"
PROXYPORT=8012
export no_proxy=localhost,127.0.0.1,http://vs-nxte-yourusername,http://vs-nxte-yourusername.net1.cec.eu.int
export http_proxy="http://${PROXYUSER}:${PROXYPASSWORD}@${PROXYHOST}:${PROXYPORT}/"
export https_proxy="http://${PROXYUSER}:${PROXYPASSWORD}@${PROXYHOST}:${PROXYPORT}/"
export HTTP_PROXY="http://${PROXYUSER}:${PROXYPASSWORD}@${PROXYHOST}:${PROXYPORT}/"
export HTTPS_PROXY="http://${PROXYUSER}:${PROXYPASSWORD}@${PROXYHOST}:${PROXYPORT}/"

Source file or logout and login again to have changes activated.