at-spi2-core software package provides Assistive Technology Service Provider Interface (dbus core), you can install in your Ubuntu 16.04 LTS (Xenial Xerus) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install at-spi2-core
at-spi2-core is installed in your system.
Make ensure the at-spi2-core package were installed using the commands given below,
$ sudo dpkg-query -l | grep at-spi2-core *
You will get with at-spi2-core package name, version, architecture and description in a table
| Distro | Ubuntu 16 04 lts xenial xerus |
| Section | Miscellaneous |
| Package | at-spi2-core |
| Version | 2.18.3-4ubuntu1 |
| Description | Assistive Technology Service Provider Interface (dbus core) |
| Sub Section | Misc |