get_template_block() - returns a part of a template

gistfile1.py

from django.template import loader, loader_tags


def get_template_block(template_name, block_name):
    """Searchs a returns a single block inside a template.
        Useful for ajax reloading inside a template.
        - template_name can be a filename or a list of filenames.
        - block_name is the name of the block to look for:
        {% block block_name %}
        This function returns a BlockNode instance, which can be rendered to
        a response, such as:
            HttpResponse(block.render(context)) """
    template = loader.get_template(template_name)
    return get_nodelist_block(template.nodelist, block_name)

def get_nodelist_block(nodelist, block_name):
    """Recursively searches the node tree to find a block named `block_name`"""
    for node in nodelist:
        if isinstance(node, loader_tags.BlockNode) and node.name == block_name:
            return node
        if node.child_nodelists:
            for attr in node.child_nodelists:
                child_nodelist = getattr(node, attr, None)
                if child_nodelist:
                    block = get_nodelist_block(child_nodelist, block_name)
                    if block:
                        return block