input: Write a python function to extract the title, meta description, and all heading tags (h1-h6) from a given URL.
  assert extract_info("Sample URL") == {"title": "Expected Title", "meta_description": "Expected Meta Description", "heading_tags": "Expected Heading Tags"}
  assert extract_info("Another Sample URL") == {"title": "Another Expected Title", "meta_description": "Another Expected Meta Description", "heading_tags": "Another Expected Heading Tags"}
output: def extract_info(url):
      import requests
      from bs4 import BeautifulSoup
  
      response = requests.get(url)
      soup = BeautifulSoup(response.content, 'html.parser')
  
      title = soup.title.string if soup.title else ''
  
      meta_description = ''
      meta_tag = soup.find('meta', attrs={'name': 'description'})
      if meta_tag and 'content' in meta_tag.attrs:
          meta_description = meta_tag['content']
  
      heading_tags = {}
      for i in range(1, 7):
          heading_tags[f'h{i}'] = [tag.get_text() for tag in soup.find_all(f'h{i}')]
  
      return {
          "title": title,
          "meta_description": meta_description,
          "heading_tags": heading_tags
      }