q3_solution

import requests
from bs4 import BeautifulSoup
import os
import json

url = 'https://en.wikipedia.org/wiki/ASEAN'
filename = 'urban_areas.json'

response = requests.get(url)
soup = BeautifulSoup(response.text, 'html.parser')

table = soup.find('table', class_='sortable wikitable plainrowheaders')

countries_dictionary = {}

for row in table.find_all('tr')[1:]:
    cols = row.find_all('td')
    city = row.find('th').text.strip()

    population = int(cols[0].text.strip().replace(',', ''))
    area = float(cols[1].text.strip().replace(',', ''))
    country = cols[2].text.strip()

    city_data = {
        'City': city,
        'Population': population,
        'Area (km²)': area,
        'Population Density': round(population / area, 2)
    }

    countries_dictionary.setdefault(country, []).append(city_data)

if os.path.exists(filename):
    with open(filename, 'r') as file:
        existing_data = json.load(file)
else:
    existing_data = {}

if existing_data != countries_dictionary:
    with open(filename, 'w') as file:
        json.dump(countries_dictionary, file, indent=1)