Peak Visitor Day for Each Trail

PandasMediumMid level~10 min

Problem

A national park logs the number of hikers counted on each trail every day. The DataFrame `trail_log` (loaded from `trail_log.csv`) has columns `(trail_id, log_date, hikers)`.

For every trail, report the day on which it recorded its highest hiker count. If the same peak count occurred on more than one day, report the earliest of those days.

Return the columns `trail_id`, `log_date`, and `hikers`.

Input data

Example rows — the live problem includes the full dataset.

trail_log

trail_id	log_date	hikers
1	2022-04-03	40
1	2022-05-09	120
1	2022-06-21	310
2	2022-07-01	88
2	2022-07-15	88

Expected output

Your answer should return 3 rows with the columns trail_id, log_date, hikers.

Starter code (Pandas (Python))

import pandas as pd

def peak_visitor_day_per_trail(trail_log) -> pd.DataFrame:
    # Your code here
    return trail_log

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