void Base::AddSpectator(Observable& observable)
{
    INFO0;
    observable.SetBranchName(BranchName(Stage::trainer));
    spectators_.emplace_back(observable);
}
void Base::AddVariable(Observable& observable)
{
    INFO0;
    observable.SetBranchName(BranchName(Stage::trainer));
    variables_.emplace_back(observable);
}