Stop being root in the middle of a script that was run with sudo

Question

There is a list of commands that only succeed when they are prefaced with sudo.
There is another list of commands that only succeed when the user runs them

Answer 1

Here is how I would run it in a script.

#! /bin/bash

if [[ $EUID -ne 0 ]]; then
   echo "This script must be run as root";
   exit 1;
else
    NON_ROOT_USER=$(who am i | awk '{print $1}');
    echo "root ran this echo.";
    sudo -u $NON_ROOT_USER echo "$NON_ROOT_USER ran this echo.";
fi

sudo ./script.sh