Countries You Can Safely Invest In — LeetCode 1501 Python Solution

Table Person: +----------------+---------+ | Column Name | Type | +----------------+---------+ | id | int | | name | varchar | | phone_number | varchar | +----------------+---------+ id is the column of unique values for this table. Each row of this table contains the name of a person and their phone number.

+----------------+---------+
| Column Name    | Type    |
+----------------+---------+
| id             | int     |
| name           | varchar |
| phone_number   | varchar |
+----------------+---------+
id is the column of unique values for this table.
Each row of this table contains the name of a person and their phone number.
Phone number will be in the form 'xxx-yyyyyyy' where xxx is the country code (3 characters) and yyyyyyy is the phone number (7 characters) where x and y are digits. Both can contain leading zeros.

import duckdb
import pandas as pd

# Pass input tables as keyword arguments matching the SQL table names.
def solution(**tables) -> pd.DataFrame:
    con = duckdb.connect()
    for name, df in tables.items():
        con.register(name, df)
    return con.execute("""SELECT country
FROM
    (
        SELECT c.name AS country, AVG(duration) AS duration
        FROM
            Person
            JOIN Calls ON id IN(caller_id, callee_id)
            JOIN Country AS c ON LEFT(phone_number, 3) = country_code
        GROUP BY 1
    ) AS t
WHERE duration > (SELECT AVG(duration) FROM Calls);""").df()