Could not get lock /var/lib/apt/lists/lock. It is held by process 1307 (packagekitd) code example
Example 1: E: Unable to acquire the dpkg frontend lock (/var/lib/dpkg/lock-frontend), is another process using it?
sudo lsof /var/lib/dpkg/lock
sudo lsof /var/lib/apt/lists/lock
sudo lsof /var/cache/apt/archives/lock
Example 2: apt lock
rm -rf /var/cache/apt/* /var/lib/dpkg/lock /var/lib/dpkg/lock-frontend \
/var/cache/debconf/ /var/lib/apt/lists/* \
/var/lib/dpkg/lock /var/lib/dpkg/lock-frontend /var/cache/debconf/