code: def _add_handler(cls, handler, fmt, level):
          
          handler.setFormatter(_get_formatter(fmt))
          if level:
              handler.setLevel(level)
          logging.root.addHandler(handler)
          cls.used_formats = ("%s %s" % (cls.used_formats or "", fmt)).strip()
          cls.handlers.append(handler)
docs: Args:
              handler (logging.Handler): Handler to decorate
              fmt (str | unicode): Format to use