Show the contents of a value expression.
The {% print %} tag is used to dump the contents of a variable in
a HTML safe way. It is very useful for debugging and inspecting
variables during template development.
For example:
{% print value %}
When value is "<b>Hello</b> world!" then the example above returns the output:
<pre>
<b>Hello</b> world!
</pre>
It can also print complex values like nested lists and tuples, for
which it uses Erlang’s io_lib:format/2 function.