code: def create_param_doc(cls, param, prefix=None):
          
          desc = cls.exclude_html_reg.sub('', param['description']).strip()
          if not desc:
              desc = "<no description>"
          name = param['name']
          if prefix:
              name = "%s[%s]" % (prefix, name)
          doc_ = ":param %s: %s; %s" % (name, desc, param['validator'])
          if param['required']:
              doc_ += " (REQUIRED)"
          else:
              doc_ += " (OPTIONAL)"
          for param in param.get('params', []):
              doc_ += "\n" + cls.create_param_doc(param, name)
          return doc_
docs: Generate documentation for single parameter of function
          :param param: dict contains info about parameter
          :param sub: prefix string for recursive purposes