old_contents: 
  #From http://stackoverflow.com/questions/2687173/django-how-can-i-get-a-block-from-a-template
  from django.template import Context
  from django.template.loader_tags import BlockNode, ExtendsNode
  
  
  class BlockNotFound(Exception):
      pass
  
  
  def _get_node(template, context=Context(), name='subject', block_lookups={}):
      for node in template:
          if isinstance(node, BlockNode) and node.name == name:
              #Rudimentary handling of extended templates, for issue #3
              for i in xrange(len(node.nodelist)):
                  n = node.nodelist[i]
                  if isinstance(n, BlockNode) and n.name in block_lookups:
                      node.nodelist[i] = block_lookups[n.name]
              return node.render(context)
          elif isinstance(node, ExtendsNode):
              lookups = dict([(n.name, n) for n in node.nodelist if isinstance(n, BlockNode)])
              lookups.update(block_lookups)
              return _get_node(node.get_parent(context), context, name, lookups)
      raise BlockNotFound("Node '%s' could not be found in template." % name)
  
new_contents: 
  #From http://stackoverflow.com/questions/2687173/django-how-can-i-get-a-block-from-a-template
  from django.template import Context
  from django.template.loader_tags import BlockNode, ExtendsNode
  
  
  class BlockNotFound(Exception):
      pass
  
  
  def _get_node(template, context=Context(), name='subject', block_lookups={}):
      for node in template.template:
          if isinstance(node, BlockNode) and node.name == name:
              #Rudimentary handling of extended templates, for issue #3
              for i in xrange(len(node.nodelist)):
                  n = node.nodelist[i]
                  if isinstance(n, BlockNode) and n.name in block_lookups:
                      node.nodelist[i] = block_lookups[n.name]
              return node.render(context)
          elif isinstance(node, ExtendsNode):
              lookups = dict([(n.name, n) for n in node.nodelist if isinstance(n, BlockNode)])
              lookups.update(block_lookups)
              return _get_node(node.get_parent(context), context, name, lookups)
      raise BlockNotFound("Node '%s' could not be found in template." % name)
  
subject: Fix 'Template is not iterable' error