### How to call a constant polynomial with lift()?

I am trying to call a constant polynomial with `lift()`

,
but I get an error. The following is a minimal example
of my input that produces an error:

```
sage: A.<x, y> = PolynomialRing(CC, 2, order='degrevlex')
sage: I = A.ideal([x + y, x
```~~- y])
~~+ y+1])
sage: A(1).lift(I)

When I input a non-constant polynomial (say, `f = `~~x^2 + y^2~~(x+y)^2

),
Sage executes `lift(I)`

as expected. I only get an error
for constant polynomials like `A(1)`

.