Chefs Who Tasted Their Own Dish

PandasEasyJunior level~10 min

Problem

You are given a DataFrame `tastings` loaded from `tastings.csv` with the columns `dish_id`, `chef_id`, `taster_id` and `taste_day`. There is no single-column key; each row means `taster_id` tasted dish `dish_id`, which was created by `chef_id`, on `taste_day`.

Find every chef who tasted at least one of their own dishes (the chef and the taster are the same person). Return one row per such chef in a single column named `id`, sorted by `id` in ascending order.

Example `tastings`:

```text
dish_id chef_id taster_id taste_day
1 5 5 2024-01-01
2 5 7 2024-01-01
3 8 8 2024-01-02
4 9 5 2024-01-03
```

Expected result is `[5, 8]`: chef 5 tasted dish 1 (their own) and chef 8 tasted dish 3 (their own).

Input data

Example rows — the live problem includes the full dataset.

tastings

dish_id	chef_id	taster_id	taste_day
1	5	5	2024-01-01
2	5	7	2024-01-01
3	8	8	2024-01-02
4	9	5	2024-01-03

Expected output

Your answer should return 2 rows with the columns id.

Starter code (Pandas (Python))

import pandas as pd

def self_tasting_chefs(tastings) -> pd.DataFrame:
    # Your code here
    return tastings

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