Parse sass on import

I have a .yml file I'm importing like this:

```
colors:
  primary: 
    base: rgb(0, 255, 200)
    dark: darken(rgb(0, 255, 200), 10%)
```

Is there anyway to get the importer to parse the sass instead of just mapping it as a string?  The `darken(rgb(0, 255, 200), 10%)` bit is not turned into a rgb or hex value from this.
