block
Define a block in a template and overrules a block from an inherited template.
The block tag is used for replacing blocks in inherited templates.
For example, when we have a template base.tpl, in which we define a block called name:
Hello {% block name %}my{% endblock %} world.
And we define a second template, page.tpl, which extends the first template:
{% extends "base.tpl" %}
{% block name %}Peter's{% endblock %}
Then the result of rendering page.tpl will be:
Hello Peter's world.
If we do not include the block definition, so page.tpl just contains the extends tag:
{% extends "base.tpl" %}
then the output will be:
Hello my world.
The name of a block must be a valid identifier, consisting of alphanumeric characters (a-z, 0-9) and the underscore charater.