Is there an elegant way to define a constant TF2?

With TF1 it’s simple: TF1(“f”, “1”);

However

```
TF2 *f2 = new TF2("f2", "1");
Error in <TF2::TF2>: function: f2/1 has 1 parameters instead of 2
```

I know I could do a formula like “x*0+y*0+1”, however I assume that does some calculations, where it could do none…