input: Write a python function to extract and print the class attribute of all div elements from a given URL using BeautifulSoup, and print the text content if the class attribute is not present.
  assert extract_div_classes('https://www.example.com') is not None
output: def extract_div_classes(url):
      import requests
      from bs4 import BeautifulSoup
      
      response = requests.get(url)
      soup = BeautifulSoup(response.content, 'html.parser')
      
      divs = soup.find_all('div')
      for div in divs:
          if 'class' in div.attrs:
              print(div['class'])
          else:
              print(div.get_text())