docs: def grok_for_node(element, default_vars):
      """Properly parses a For loop element"""
      if isinstance(element.iter, jinja2.nodes.Filter):
          if element.iter.name == 'default' \
             and element.iter.node.name not in default_vars:
              default_vars.append(element.iter.node.name)
  
          default_vars = default_vars + grok_vars(element)
  
      return default_vars