package:docker.io:17.12.1-0ubuntu1
Setting up docker.io (17.12.1-0ubuntu1) ...
locale: Cannot set LC_CTYPE to default locale: No such file or directory
locale: Cannot set LC_MESSAGES to default locale: No such file or directory
locale: Cannot set LC_ALL to default locale: No such file or directory
addgroup: The group `docker' already exists and is not a system group. Exiting.
dpkg: error processing package docker.io (--configure):
 installed docker.io package post-installation script subprocess returned error exit status 1