input: Write a function to implement a web scraper in Python to extract the top ten trending YouTube videos. The function should make a request to the trending page, parse the content using BeautifulSoup, and then print the titles of the top ten trending videos. If no videos are found or there are fewer than ten videos, the function should handle this gracefully.
  assert extract_trending_videos()==["Video 1 Title", "Video 2 Title", "Video 3 Title", "Video 4 Title", "Video 5 Title", "Video 6 Title", "Video 7 Title", "Video 8 Title", "Video 9 Title", "Video 10 Title"]
  assert extract_trending_videos()==[]
  assert extract_trending_videos()==["Video A", "Video B", "Video C", "Video D", "Video E", "Video F", "Video G", "Video H", "Video I", "Video J"]
output: def extract_trending_videos():
      import requests
      from bs4 import BeautifulSoup
      url = "https://www.youtube.com/feed/trending"
      response = requests.get(url)
      soup = BeautifulSoup(response.content, 'html.parser')
      video_titles = []
      for title in soup.find_all('a', {'class': 'yt-simple-endpoint style-scope ytd-video-renderer'}):
          video_titles.append(title.get_text().strip())
          if len(video_titles) == 10:
              break
      return video_titles[:10]