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mymaster.html

views.py

template.html

<!DOCTYPE html>
<html>
<body>

<h1>Welcome</h1>

{% block mymessage %}
{% endblock %}

<p>Check out the two templates to see what they look like, and views.py to see the reference to the child template.</p>

</body>
</html>

from django.http import HttpResponse
from django.template import loader

def testing(request):
  template = loader.get_template('template.html')
  return HttpResponse(template.render())

{% extends 'mymaster.html' %}

{% block mymessage %}
  <p>This page has a master page</p>
{% endblock %}