This is an outstanding snippet and I'd vote for it to be included int…

…o core, but there's a pointless .render() on line 47, presumably left over from debugging.

This is actually a bug because if the entire template requires a variable and the block does not, render_block_to_string will fail without that unnecessary variable.

template.py

@@ -44,7 +44,6 @@ def render_block_to_string(template_name, block, dictionary=None, context_instan
         context_instance.update(dictionary)
     else:
         context_instance = Context(dictionary)
-    t.render(context_instance)
     return render_template_block(t, block, context_instance)
 
 def direct_block_to_template(request, template, block, extra_context=None, mimetype=None, **kwargs):