/bin/sh: 1: sudo: not found when running dockerfile

FROM ubuntu

RUN sudo apt-get update

RUN sudo apt-get install -y wget

CMD wget -O- -q http://ifconfig.me/ip

THis is the content of my dockerfile. When i am running the dockerfile to build a docker image, i get the below error:

/bin/sh: 1: sudo: not found

Can you please help me in solving the above error?

Source: StackOverflow