invert if, how to explain .IsNotNull() should become .IsNull()

Hi,

I'm working with the Methode Extensions

myObject.IsNotNull() for myObject != null and

myObject.IsNull() for myObject == null

So, on doing "invert if statement to reduce nesting"
myObject.IsNotNull() becomes !myObject.IsNotNull()

That's obvious not really a beauty.

I'm shure there is a way to explain ReSharper that IsNotNull() is the invers of IsNull().
[Attribute...] ???

How does it work?

tia Ernst