dpkg: error: dpkg frontend lock is locked by another process

dpkg_frontend_lock_error.sh

#!/bin/bash

# dpkg: error: dpkg frontend lock is locked by another process
# Ref: https://askubuntu.com/a/291584

# Check PID of the running dpkg process
lsof /var/lib/dpkg/lock

# See status of the process
ps cax | grep ${PID}

# If it's still running:
kill ${PID}
kill -9 ${PID}

# Check kill result
ps cax | grep ${PID}

# Remove lock file
sudo rm /var/lib/dpkg/lock

# Fix dpkg
sudo dpkg --configure -a