sudo apt-get update

W: Target Packages (partner/binary-amd64/Packages) is configured multiple times in /etc/apt/sources.list:41 and /etc/apt/sources.list.d/xenial-partner.list:4
W: Target Packages (partner/binary-i386/Packages) is configured multiple times in /etc/apt/sources.list:41 and /etc/apt/sources.list.d/xenial-partner.list:4
W: Target Packages (partner/binary-all/Packages) is configured multiple times in /etc/apt/sources.list:41 and /etc/apt/sources.list.d/xenial-partner.list:4

sudo apt update

#OR
sudo apt-get update