casey@casey-MacBookPro:~$ sudo apt-add-repository ppa:ehoover/compholio
[sudo] password for casey:
You are about to add the following PPA to your system:

 More info: https://launchpad.net/~ehoover/+archive/compholio
Press [ENTER] to continue or ctrl-c to cancel adding it

gpg: keyring `/tmp/tmpdeqe77/secring.gpg' created
gpg: keyring `/tmp/tmpdeqe77/pubring.gpg' created
gpg: requesting key 1F691896 from hkp server keyserver.ubuntu.com
gpg: /tmp/tmpdeqe77/trustdb.gpg: trustdb created
gpg: key 1F691896: public key "Launchpad compholio" imported
gpg: Total number processed: 1
gpg:               imported: 1  (RSA: 1)
OK
casey@casey-MacBookPro:~$ sudo apt-get update
E: Could not get lock /var/lib/apt/lists/lock - open (11: Resource temporarily unavailable)
E: Unable to lock directory /var/lib/apt/lists/
casey@casey-MacBookPro:~$