Based on the unique values identified in the 'country' column of the dataset, here's the issue discovered based on the provided \(\text{<hint>}\):

## First Issue:

- **Issue**: Abnormal country code value
- **Evidence**: "N,0\""
- **Description**: The dataset contains an abnormal country code "N,0\"". This does not correspond to a valid ISO 3166-1 alpha-2 country code and likely represents missing or malformed data.

## Recommendation:

Given the abnormal country code identified, a review and correction (or clarification of meaning) of these entries are recommended to ensure data consistency and accuracy.