Django: how to set up the site name and show it at the end of all pages title


For example, there are 3 html templates with different titles:

<title>Page1</title>
<title>Page2</title>
<title>Page3</title>

How to append all the titles with the site name at the end using variable (or other ways)?:

<title>Page1 - {{Here is the configurable Site Name}}</title>
<title>Page2 - {{Here is the configurable Site Name}}</title>
<title>Page3 - {{Here is the configurable Site Name}}</title>