Poll whether exam vacancies are still available for Goethe B1 exam in Münchner Volkshochschule, show message if not

poll_exam_vacancies.py

import requests
import subprocess
import datetime
from bs4 import BeautifulSoup

def are_there_free_places(html):
    soup = BeautifulSoup(html, 'html.parser')
    places = soup.find(**{'data-label': 'Plätze: '}).text.strip() 
    return places == 'Noch Plätze frei'

def notify_send(message):
    subprocess.check_call(['notify-send', '-t', '0', message], env={'DISPLAY': ':0'})

url = 'https://www.mvhs.de/programm/deutsch-integration/goethe-zertifikat-b1.20152/O671220'
html = requests.get(url).text
places_free = are_there_free_places(html)
if not places_free:
    notify_send('Few places left')

with open('log.txt', 'a') as fd:
    time = datetime.datetime.now().isoformat()
    fd.write(f'{time}\t{places_free}\n')