$ uber time '123 anywhere st'
    No API key found. Please create one using the
    instructions at <site> and call 'uber set-key <key>'
    $ uber set-key <key> # writes <key> to a file in home dir or a .gitignore location in the repo
    Well done!
    $ uber time '123 anywhere st' # reads <key> from file, works as you have it
    ...