Library Checkouts by Weekday and Genre

PandasHardSenior level~10 min

Problem

A public library tracks how many copies of each title were checked out.

You are given two DataFrames:

`titles` (one row per title)
- `title_id` - title identifier
- `title_name` - title name
- `genre` - the genre of the title

`checkouts` (one row per checkout)
- `checkout_id` - checkout identifier
- `patron_id` - the patron who checked the title out
- `taken_on` - the date of the checkout
- `title_id` - the title that was taken
- `copies` - how many copies were taken in that checkout

For every genre, report the total number of copies checked out on each day of the week. Return one row per genre with columns `genre`, `Monday`, `Tuesday`, `Wednesday`, `Thursday`, `Friday`, `Saturday`, `Sunday`. A genre with no checkouts on a given day must show 0 for that day, and every genre in the catalog must appear even if it had no checkouts at all. Order the result by `genre`.

Input data

Example rows — the live problem includes the full dataset.

titles

title_id	title_name	genre
f1	Tide Lines	Fiction
f2	Glass Harbor	Fiction
c1	Star Patrol	Comic
c2	Night Vault	Comic
m1	Engine Care	Manual

checkouts

checkout_id	patron_id	taken_on	title_id	copies
1	1	2022-06-01	f1	10
2	2	2022-06-01	f2	10
3	3	2022-06-02	f1	5
4	4	2022-06-03	c1	5
5	5	2022-06-05	c2	7

Expected output

Your answer should return 4 rows with the columns genre, Monday, Tuesday, Wednesday, Thursday, Friday, Saturday, Sunday.

Starter code (Pandas (Python))

import pandas as pd

def library_checkouts_by_weekday_and_genre(titles, checkouts) -> pd.DataFrame:
    # Your code here
    return titles

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