code: def function(self, rule, args, **kwargs):
          
          return '<div class="pynspect-rule-function"><h3 class="pynspect-rule-function-name">{}</h3><ul class="pynspect-rule-function-arguments>{}</ul></div>'.format(rule.function, ''.join(['<li class="pynspect-rule-function-argument">{}</li>'.format(v) for v in args]))
docs: Callback method for rule tree traversing. Will be called at proper time
          from :py:class:`pynspect.rules.FunctionRule.traverse` method.
  
          :param pynspect.rules.Rule rule: Reference to rule.
          :param args: Optional function arguments.
          :param dict kwargs: Optional callback arguments.