code: def _error_code_to_str(mod, type_, code):
      
      (_, c_name) = _get_error_names(mod, type_, code)
      return '%s(%d)' % (c_name, code)
docs: This method is registered as ofp_error_code_to_str(type_, code) method
      into ryu.ofproto.ofproto_v1_* modules.
      And this method returns the error code as a string value for given
      'type' and 'code' defined in ofp_error_msg structure.
  
      Example::
  
          >>> ofproto.ofp_error_code_to_str(4, 9)
          'OFPBMC_BAD_PREREQ(9)'