input: Write a function to retrieve and print the text of all articles linked from a given Wikipedia page.
  assert get_article_texts('https://en.wikipedia.org/wiki/Machine_learning') is None
  assert get_article_texts('https://en.wikipedia.org/wiki/Artificial_intelligence') is None
  assert get_article_texts('https://en.wikipedia.org/wiki/Data_science') is None
output: def get_article_texts(url):
      import requests
      from bs4 import BeautifulSoup
      
      response = requests.get(url)
      if response.status_code != 200:
          return None
      
      soup = BeautifulSoup(response.content, 'html.parser')
      links = soup.find_all('a', href=True)
      
      base_url = 'https://en.wikipedia.org'
      
      for link in links:
          href = link['href']
          if href.startswith('/wiki/') and not ':' in href:
              article_url = base_url + href
              article_response = requests.get(article_url)
              if article_response.status_code == 200:
                  article_soup = BeautifulSoup(article_response.content, 'html.parser')
                  paragraphs = article_soup.find_all('p')
                  for paragraph in paragraphs:
                      print(paragraph.get_text())