```json
{
	"no": ["no"],
	"yes": ["yes"]
}
```
Since the feature "n_p_ecg_p_07" represents whether the patient has LBBB (anterior branch) on ECG at the time of admission to the hospital, the possible values for this feature are "no" and "yes". If the patient has LBBB, it is possible that they may have chronic heart failure (target class "yes"), and if they do not have LBBB, it is possible that they may not have chronic heart failure (target class "no").