Course of Each Learner's First Enrollment

PandasEasyJunior level~10 min

Problem

An online learning platform logs each course a learner enrolled in, and when.

DataFrame: `enrollments` (from `enrollments.csv`)

| Column | Type |
|---------------|--------|
| learner_id | int |
| course_id | int |
| enroll_date | object |
| hours_studied | int |

Write a function that reports, for each learner, the `course_id` they enrolled in on their **earliest** `enroll_date`. Return columns `learner_id` and `course_id`, in any order.

Input data

Example rows — the live problem includes the full dataset.

enrollments

learner_id	course_id	enroll_date	hours_studied
1	20	2023-01-05	5
1	21	2023-03-02	6
2	30	2023-02-18	1
3	11	2023-01-09	0
3	44	2023-06-07	5

Expected output

Your answer should return 3 rows with the columns learner_id, course_id.

Starter code (Pandas (Python))

import pandas as pd

def first_course(enrollments: pd.DataFrame) -> pd.DataFrame:
    # Your code here
    return enrollments

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