[Feature Request] Add a NOT operator that can be used with the current Variables

[ArrowM]

Let's say I have a Lora wildcard __loras__ and I want to combine them to get interesting weight combinations. My naive implementation of combining them is:

<lora:__loras__:0.3><lora:__loras__:0.7>

This works okay, but what if I always want 2 unique loras without the chance of both wildcards evaluating to the same thing.
One solution would be adding a NOT operator such as |!, since wildcard evaluations can already be stored as variables.

<lora:{ L1 =! __loras__ }:0.3><lora:{__loras__ |! L1 }:0.7>