parameters: (self, transport, err_msg)
docstring: Send error message to client
          @param transport: transport connection to client 
          @type  transport: Transport
          @param err_msg: error message to send to client
          @type  err_msg: str
docstring_summary: Send error message to client
docstring_tokens: Send error message to client
function: def _write_service_error(self, transport, err_msg):
          """
          Send error message to client
          @param transport: transport connection to client 
          @type  transport: Transport
          @param err_msg: error message to send to client
          @type  err_msg: str
          """
          transport.write_data(struct.pack('<BI%ss'%len(err_msg), 0, len(err_msg), err_msg))
function_tokens: def _write_service_error ( self , transport , err_msg ) : transport . write_data ( struct . pack ( '<BI%ss' % len ( err_msg ) , 0 , len ( err_msg ) , err_msg ) )