Install .Net Core 3.1 preview 3 in Ubuntu

$: cd ~/
$: mkdir tmp
$: cd tmp
$: wget https://dotnetwebsite.azurewebsites.net/download/dotnet-core/scripts/v1/dotnet-install.sh
$: chmod +x dotnet-install.sh
$: ./dotnet-install.sh -Version 3.1.100-preview3-014645
$: export PATH="$HOME/.dotnet:$PATH"