input: Write a python function to extract the first Google Drive link from the given HTML content using the provided LINK_FREE_PATTERN regex pattern.
  assert extract_link('<html>...</html>') is None
  assert extract_link('<html>...<a href="https://drive.google.com/uc?id=some_id&export=download">...</a>...</html>') == 'https://drive.google.com/uc?id=some_id&export=download'
  assert extract_link('<html>...<a href="https://drive.google.com/uc?id=another_id&export=download">...</a>...</html>') == 'https://drive.google.com/uc?id=another_id&export=download'
output: import re
  
  def extract_link(html_content):
      LINK_FREE_PATTERN = r'https://drive\.google\.com/uc\?id=[^"&]+&export=download'
      match = re.search(LINK_FREE_PATTERN, html_content)
      if match:
          return match.group(0)
      return None