Running Total of Donations per Donor
Problem
A charity records each donation a supporter makes on a given date.
DataFrame: `gifts` (from `gifts.csv`)
| Column | Type |
|-------------|--------|
| donor_id | int |
| campaign_id | int |
| gift_date | object |
| amount | int |
Write a function that reports, for each donor and each of their gift dates, the **cumulative total** the donor has given up to and including that date. Return columns `donor_id`, `gift_date`, and `total_so_far`, in any order.
Input data
Example rows — the live problem includes the full dataset.
| donor_id | campaign_id | gift_date | amount |
|---|---|---|---|
| 1 | 2 | 2019-03-01 | 5 |
| 1 | 2 | 2019-05-02 | 6 |
| 1 | 3 | 2020-06-25 | 1 |
| 3 | 1 | 2019-03-02 | 0 |
| 3 | 4 | 2021-07-03 | 5 |
Expected output
Your answer should return 5 rows with the columns donor_id, gift_date, total_so_far.
Starter code (Pandas (Python))
import pandas as pd
def running_total(gifts: pd.DataFrame) -> pd.DataFrame:
# Your code here
return giftsSolve this Pandas question free
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