block Template Tag
Example
Define a section in a master template that should be replaced by a section in a child template:
<!DOCTYPE html>
<html>
<body>
<h1>Welcome</h1>
{% block userinfo %}
  <h2>Not registered yet</h2>
{% endblock %}
</body>
</html>
Definition and Usage
The block tag  has two functions:
- It is a placeholder for content.
- It is content that will replace the placeholder.
In master templates the block tag 
is a placeholder that will be replaced by a block in a child template with the 
same name.
In child templates the block tag is 
content that will replace the placeholder in the master template with the same 
name.
In the example above you see the content of a master template, it has a block 
called userinfo. This block will be replaced 
with a block called userinfo in a child template:
Example
This is a child template that refers to a master template via the
extend tag:
{% extends "mymaster.html" %}
{% block userinfo %}
  <h2>John Doe</h2>
  <p>Explorer of life.</p>
{% endblock %}
Syntax
{% block name %}
  ...
{% endblock %}
Parameters
| Value | Description | 
|---|---|
| name | Specifies that name of the block. | 
 
 
