code: func RunMutation(c context.Context, m Mutation) error {
  	cfg := getConfig(c)
  	shardSet, _, _, err := enterTransactionMutation(txnBuf.FilterRDS(c), cfg, m, 0)
  	if err != nil {
  		return err
  	}
  	fireTasks(c, cfg, shardSet, true)
  	return nil
  }
docs: // RunMutation immediately runs the Mutation `m` in a transaction. This method
  // should be used to start a tumble chain when you have transactional checks
  // to do (e.g. `m` implements the first transactional link in the chain).
  //
  // Usually this is called from your application's handlers to begin a tumble
  // state machine as a result of some API interaction.