A shortcut for bash using tt

I heavily use the ~/tmp directory of my computer and have the habit of moving to it, creating a new temporary directory, moving into that, and creating a short-lived project. Finally I automated that and have been actually using the automation:

I wrote this tiny zsh function called tt that creates a new directory in ~/tmp/ and cd’s to it:

tt() {
    RANDOM_DIR=$(date +%Y%m%d%H%M%S)-$RANDOM
    mkdir -p ~/tmp/"$RANDOM_DIR"
    cd ~/tmp/"$RANDOM_DIR" || return
}

This goes in my .zshrc.