Let us start an interactive session (e.g. with python or ipython) and import Aesara.

>>> from aesara import *

Several of the symbols you will need to use are in the tensor subpackage of Aesara. Let us import that subpackage under a handy name like at (the tutorials will frequently use this convention).

>>> import aesara.tensor as at

If that succeeded you are ready for the tutorial, otherwise check your installation (see Installing Aesara).

Throughout the tutorial, bear in mind that there is a Glossary as well as index and modules links in the upper-right corner of each page to help you out.