Tell me the difference

tell_me_the_difference.py

import requests
import urllib.request
import time
from bs4 import BeautifulSoup

import difflib
import os
import smtplib
import email.message
import io
from requests_html import HTMLSession

import sys

things_to_test = [
        #{
        #'name': 'clock',
        #'url': 'https://free-onlineclock.com/online-clock',
        #'div': 'vue_clock'
        #}, 
]

local_mail = 'localhost@localhost'
script_folder = os.path.dirname(os.path.realpath(__file__))

def send_self_local_mail(subject, body):
    sender_mail = local_mail
    receivers_mail = [local_mail]

    m = email.message.Message()
    m['From'] = local_mail
    m['To'] = local_mail
    m['Subject'] = subject
    m.set_payload(body);
    m = m.as_string()
    try:
        smtpObj = smtplib.SMTP('localhost')
        smtpObj.sendmail(sender_mail, receivers_mail, m)
        print("Successfully sent email")
    except Exception as e:
        print("Error: unable to send email")
        print(str(e))
        _, _, stack = sys.exc_info()
        print(str(stack))


def tell_me_the_difference(url, div_id, name):
    print('Tell me the difference\nname={}\nurl={}\nid={}'.format(name, url, div_id))
    session = HTMLSession()

    try:
        r = session.get(url)

        try:
            r.raise_for_status()
        except ValueError as e:
            raise('Dead link')

        r.html.render(sleep = 2, timeout = 20)  # this call executes the js in the page

        #soup = BeautifulSoup(response.text, 'html.parser')
        details = r.html.find('#{}'.format(div_id))[0].text.replace('\t', '    ').splitlines()

        #details = str(soup.findAll(id=div_id)[0]).replace('\t', '    ').splitlines()
        file_path = os.path.join(script_folder, name)

        # Write it in a file the first time.
        if os.path.exists(file_path):
            previous_details = None
            with io.open(file_path, 'r', encoding='utf-8') as file:
                previous_details = file.read().replace('\t', '    ').splitlines()

            diff = difflib.ndiff(details, previous_details)
            changes = [l for l in diff if l.startswith('+ ') or l.startswith('- ')]
            has_changes = len(changes) > 0
            pretty_changes = '\n'.join(changes)
            print('DIFF?: ', has_changes)

            if has_changes:
                send_self_local_mail('{} diff'.format(name), '{}\n\n{}'.format(url, pretty_changes))

        with io.open(file_path, 'w', encoding='utf-8') as file:
            file.write('\n'.join(details))
    except Exception as e:
        print('FAILURE')
        print(str(e))
        _, _, stack = sys.exc_info()
        send_self_local_mail('{} failed'.format(name), '{}\n\n{}\n\n{}'.format(url, str(e), stack))

if __name__ == '__main__':

    for thing in things_to_test:
        url = thing['url']
        div_id = thing['div']
        name = thing['name']

        tell_me_the_difference(url, div_id, name)

        time.sleep(10)

    sys.exit(0)