Quick-and-dirty solution: Find a tab somewhere else, then copy-paste.
Chances are that you already have a tab character in the file you are editing, but if not you can generate one in another application or text editor.
You can also generate a tab programmatically in a bash shell with the following command (the brackets are optional):
echo -e [\\t]
For your more immediate needs, I have inserted a tab character below…
There is a tab character between these brackets: [ ]
Another approach is to change the tab mode temporarily, as shown here.