Daily Net Inventory Movement

PandasMediumMid level~10 min

Problem

A warehouse logs how many units moved in and out of stock each day.

DataFrame `movements` (from `movements.csv`) has columns `move_day` (date), `direction` (either `'inbound'` or `'outbound'`), and `units`. Each row gives the total units moved in that direction on that day; `(move_day, direction)` is unique.

For each day, report the net change in stock, defined as inbound units minus outbound units. Name the column `net_change` and order the result by `move_day`.

Input data

Example rows — the live problem includes the full dataset.

movements

move_day	direction	units
2021-09-01	inbound	10
2021-09-01	outbound	8
2021-09-02	inbound	15
2021-09-02	outbound	15
2021-09-03	inbound	20

Expected output

Your answer should return 4 rows with the columns move_day, net_change.

Starter code (Pandas (Python))

import pandas as pd

def daily_net_movement(movements) -> pd.DataFrame:
    # Your code here
    return movements

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