Collaborator Pairs With No Shared Collaborator

PandasMediumMid level~10 min

Problem

A DataFrame `collabs` records direct collaborations between researchers as undirected pairs: each row has two researcher ids `person_a` and `person_b` who have worked together. A collaboration goes both ways, so if `person_a` worked with `person_b`, then `person_b` also worked with `person_a`.

Find every collaboration pair where the two researchers share no common collaborator -- there is no third researcher who has worked with both members of the pair. Return a DataFrame with columns `person_a` and `person_b` for each such pair, ordered by `person_a` then `person_b`.

Input data

Example rows — the live problem includes the full dataset.

collabs

person_a	person_b
1	2
2	3
2	4
1	5
6	7

Expected output

Your answer should return 2 rows with the columns person_a, person_b.

Starter code (Pandas (Python))

import pandas as pd

def lonely_pairs(collabs) -> pd.DataFrame:
    # Your code here
    return collabs

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