$ sudo apt-get update
$ sudo apt-get install localechooser-data 

localechooser-data is installed in your system.

Make ensure the localechooser-data package were installed using the commands given below,

$ sudo dpkg-query -l | grep localechooser-data *

You will get with localechooser-data package name, version, architecture and description in a table

localechooser-data package basic information: