input: from typing import List
  
  def retrieve_recent_articles(url: str, num_articles: int) -> List[str]:
      """Retrieve the most recent articles from a news website.
      >>> retrieve_recent_articles('http://example.com/news', 10)
      ['Text of the first article', 'Text of the second article', ..., 'Text of the tenth article']
      """
      import requests
      from bs4 import BeautifulSoup
      
      # Get the source code from the URL
      html_content = requests.get(URL).text
      
      # Parse the HTML content
      soup = BeautifulSoup(html_content, "lxml")
      
      # Retrieve all articles
      articles = soup.find_all('article')
      
      # Return the text of the first num_articles articles
      return [article.text for article in articles[:num_articles]]
output:     import requests
      from bs4 import BeautifulSoup
      
      # Get the source code from the URL
      html_content = requests.get(url).text
      
      # Parse the HTML content
      soup = BeautifulSoup(html_content, "lxml")
      
      # Retrieve all articles
      articles = soup.find_all('article')
      
      # Return the text of the first num_articles articles
      return [article.text for article in articles[:num_articles]]