Based on my prior knowledge and analysis, I can provide the following dictionary:

```json
{
	"no": ["no"],
	"yes": ["yes"]
}
```

Since GT_POST is a categorical variable with only two categories ('no' and 'yes'), the only possible values for both target classes are 'no' and 'yes'. Thus, the feature GT_POST can only take these two values and there is a clear relationship between the feature and the task. If the GT_POST value is 'yes', it indicates the presence of paroxysms of ventricular tachycardia at the time of admission to the intensive care unit, which could be a potential indicator of chronic heart failure.