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IC05 · Products / sales · ~10–15 min

Who meets both conditions?

selection · ranking · summaries

Ranked shortlist

The question

A product team needs the three largest available order lines from the East region.

df Ranked shortlist

Your inputs

df

One row is an order line. in_stock determines availability; quantity counts units, not distinct products.

Field meanings and units
order_id
Order or order-line identifier, as defined by this brief.
product
Recorded product label.
category
Product category.
region
Sales region.
quantity
Number of units.
unit_price
Dollars per unit.
discount
Discount in dollars for the whole order line.
in_stock
Whether the order line is marked available.
df · first 5 of 18 rows
order_idproductcategoryregionquantityunit_pricediscountin_stock
P001" Notebook "PaperEast23.50false
P002PENWritingWest51.2Nonetrue
P003" pencil"WritingEast30.80.5true
P004Note-bookPaperWest43.51true
P005" Notebook "PaperEast13.50true
View all 18 rows
df · complete input
order_idproductcategoryregionquantityunit_pricediscountin_stock
P001" Notebook "PaperEast23.50false
P002PENWritingWest51.2Nonetrue
P003" pencil"WritingEast30.80.5true
P004Note-bookPaperWest43.51true
P005" Notebook "PaperEast13.50true
P006PENWritingWest61.2Nonefalse
P007" pencil"WritingEast20.80.5true
P008Note-bookPaperWest83.51true
P009" Notebook "PaperEast23.50true
P010PENWritingWest51.2Nonetrue
P011" pencil"WritingEast30.80.5false
P012Note-bookPaperWest43.51true
P013" Notebook "PaperEast13.50true
P014PENWritingWest61.2Nonetrue
P015" pencil"WritingEast20.80.5true
P016Note-bookPaperWest83.51false
P017" Notebook "PaperEast23.50true
P018PENWritingWest51.2Nonetrue

The editable setup in Your Python creates these inputs when you run it.

Your task · Who meets both conditions?

A product team needs the three largest available order lines from the East region.

shortlistDataFrameunitsnumber

Deliverables

Make the outputs listed below. Use each name exactly as shown. Then choose Check answer.

Python name key

Teal outlines name table columns. Violet left rules name Python objects. Dotted rules mark syntax, functions and parameters. Use each name exactly as shown.

  1. Qualifying shortlistOutputshortlistDataFrame
    1. Create shortlist from in_stock records in region East.
    2. Take the top three by quantity descending, breaking ties by order_id ascending.
    3. Keep order_id, product and quantity.
  2. Units representedOutputunitsnumber
    1. Store the total quantity in the shortlist as units.

Data policy Keep all supplied source tables unchanged. Work on separate outputs.

Help Hints & explained solution

Choose the amount of help you need. Opening one hint does not reveal the others.

Hint 1 — Think

Should ranking happen before or after eligibility is decided?

Hint 2 — Tools

Boolean selection, sort_values(), head() and sum()

Revisit: Combine conditions · Sort the table · Take the first look · Answer one numerical question

Hint 3 — Approach

Restrict to eligible records, rank with the stated tie-break, retain three, and total only their quantities.

Explained solution

Add these lines below # Your work in the editor. The supplied input setup is already there.

shortlist = (
    df.loc[df.in_stock & (df.region == 'East'), ['order_id', 'product', 'quantity']]
    .sort_values(['quantity', 'order_id'], ascending=[False, True])
    .head(3)
)
units = shortlist.quantity.sum()
shortlist
View supplied setup

This code is already at the top of the editor.

import pandas as pd

# Supplied input: df (18 rows)
df = pd.DataFrame(
    [
        ('P001', ' Notebook ', 'Paper', 'East', 2, 3.5, 0, False),
        ('P002', 'PEN', 'Writing', 'West', 5, 1.2, None, True),
        ('P003', ' pencil', 'Writing', 'East', 3, 0.8, 0.5, True),
        ('P004', 'Note-book', 'Paper', 'West', 4, 3.5, 1, True),
        ('P005', ' Notebook ', 'Paper', 'East', 1, 3.5, 0, True),
        ('P006', 'PEN', 'Writing', 'West', 6, 1.2, None, False),
        ('P007', ' pencil', 'Writing', 'East', 2, 0.8, 0.5, True),
        ('P008', 'Note-book', 'Paper', 'West', 8, 3.5, 1, True),
        ('P009', ' Notebook ', 'Paper', 'East', 2, 3.5, 0, True),
        ('P010', 'PEN', 'Writing', 'West', 5, 1.2, None, True),
        ('P011', ' pencil', 'Writing', 'East', 3, 0.8, 0.5, False),
        ('P012', 'Note-book', 'Paper', 'West', 4, 3.5, 1, True),
        ('P013', ' Notebook ', 'Paper', 'East', 1, 3.5, 0, True),
        ('P014', 'PEN', 'Writing', 'West', 6, 1.2, None, True),
        ('P015', ' pencil', 'Writing', 'East', 2, 0.8, 0.5, True),
        ('P016', 'Note-book', 'Paper', 'West', 8, 3.5, 1, False),
        ('P017', ' Notebook ', 'Paper', 'East', 2, 3.5, 0, True),
        ('P018', 'PEN', 'Writing', 'West', 5, 1.2, None, True),
    ],
    columns=['order_id', 'product', 'category', 'region', 'quantity', 'unit_price', 'discount', 'in_stock'],
)

Why these steps exist

  • Eligibility comes before ranking: unavailable products must not occupy a shortlist place.
  • The total uses just the three selected lines, and the ID tie-break makes the handoff deterministic.

Another valid approach

You may sort in stages or with multiple keys, provided ties are resolved before selecting three records.

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