code: func (c *Comm) DispatchSubmit(ctx context.Context, request *orderer.SubmitRequest) error {
  	reqCtx, err := c.requestContext(ctx, request)
  	if err != nil {
  		return err
  	}
  	return c.H.OnSubmit(reqCtx.channel, reqCtx.sender, request)
  }
docs: // DispatchSubmit identifies the channel and sender of the submit request and passes it
  // to the underlying Handler