Based on prior knowledge, we can analyze the relationship between the "endocr_02" feature, which represents obesity in the patient's medical history, and the presence of chronic heart failure.

To analyze the relationship, we can compare the distribution of "endocr_02" values for the two target classes: "no" (no chronic heart failure) and "yes" (chronic heart failure). By looking at the distribution, we can assess whether there are any patterns or tendencies that suggest a relationship between obesity and chronic heart failure.

Let's create a dictionary to summarize the relationships:

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

Based on the analysis, the "endocr_02" feature has a clear relationship with chronic heart failure. For the target class "no" (no chronic heart failure), the only possible value of "endocr_02" is "no". However, for the target class "yes" (chronic heart failure), both "no" and "yes" are possible values for "endocr_02".

Please note that this analysis assumes that the given feature "endocr_02" is the only predictor being considered and other factors related to chronic heart failure might still influence the prediction.