$ cat /home/ubuntu/alexmoldovan-key
ssh-rsa AAAAB3NzaC1yc2EAAAABIwAAAQEA1Azr7CIswDtHtGxE0LqqbwJwnn0AsHepFYXpB+dabXIrTdKkIxkOCZdkFl+uqUvN8No69NzOCUjLEuF7sX6Pj1B/hJ3RaJC3p1J4C+REJeoxogXMon+j3ZbfnKr3MAwCcsm5/wz+rz8Au3PWXA7BvoeBOYWS6BkXITvAl3DWmTi4DoK2fGhdD+W9RIrhEUEZLsDnj7kfdcxq4DrXFZt5s42BHLiSJE5EQifFwogKGN1RUhqGsSC1+zGYNlQ5cQytfGD7Oxj0uEU/nX7wCeUBX0DPNT3vTfctYZYEIIT7T3RHe+OIjT+y8Ug9RRapEKF+v0hjp+WcpzuiAjU/aT55dw== alex@alex-desktop

$ juju authorised-keys add /home/ubuntu/alexmoldovan-key
cannot add key "/home/ubuntu/alexmoldovan-key": invalid ssh key: /home/ubuntu/alexmoldovan-key

$ juju authorised-keys import lp:alexmoldovan                                                                                                                                             

$ juju add-machine
created machine 11

$ juju ssh 11 'grep alex .ssh/authorized_keys'                                                                                                                              
Warning: Permanently added '10.0.3.200' (ECDSA) to the list of known hosts.
ssh-rsa AAAAB3NzaC1yc2EAAAABIwAAAQEA1Azr7CIswDtHtGxE0LqqbwJwnn0AsHepFYXpB+dabXIrTdKkIxkOCZdkFl+uqUvN8No69NzOCUjLEuF7sX6Pj1B/hJ3RaJC3p1J4C+REJeoxogXMon+j3ZbfnKr3MAwCcsm5/wz+rz8Au3PWXA7BvoeBOYWS6BkXITvAl3DWmTi4DoK2fGhdD+W9RIrhEUEZLsDnj7kfdcxq4DrXFZt5s42BHLiSJE5EQifFwogKGN1RUhqGsSC1+zGYNlQ5cQytfGD7Oxj0uEU/nX7wCeUBX0DPNT3vTfctYZYEIIT7T3RHe+OIjT+y8Ug9RRapEKF+v0hjp+WcpzuiAjU/aT55dw== Juju:alex@alex-desktop # ssh-import-id lp:alexmoldovan
Connection to 10.0.3.200 closed.