How do I reference another value in the current SASS map/dictionary?

I have a SASS map of colors, and I want some of the colors to just reference another color from the map.

For example

$colors: (
     special-red: #a82523,
     red: special-red
)

However, when I run this, the value of map-get($colors, red) is literally special-red. I want the value to be #a82523.

How do you do this?

it's not possible, to add a key when your map is not event initialized. You can assign the value to a variable $special-red: #a82523; and then assign that in the map

$special-red: #a82523;
$colors: (
     special-red: $special-red,
     red: $special-red
)

But if you really want to do that, then you can create a mixin and look up through that

$colors: (
    special-red: #009CDC,
    red: special-red
);

@mixin themeColor1($color) {
  $mapColor: map-get($colors, $color);
  @if map-has($mapColor) {
    color: map-get($colors, $mapColor)
  } @else {
    color: map-get($colors, $color)
  }
}

.my-class {
  @include themeColor1(red);
}

.my-class2 {
  color: map-get($colors, special-red);
}

But my recommendation is approach 1, set variables