import requests  import re  try:      from urllib.parse import urljoin  except ImportError:      from urlparse import urljoin    # regex  email_re = re.compile(r'([\w\.,]+@[\w\.,]+\.\w+)')  link_re = re.compile(r'href="(.*?)"')      def crawl(url):        result = set()        req = requests.get(url)        # Check if successful      if(req.status_code != 200):          return []        # Find links      links = link_re.findall(req.text)        print("\nFound {} links".format(len(links)))        # Search links for emails      for link in links:            # Get an absolute URL for a link          link = urljoin(url, link)            # Find all emails on current page          result.update(email_re.findall(req.text))        return result    if __name__ == '__main__':      emails = crawl('http://www.realpython.com')        print("\nScrapped e-mail addresses:")      for email in emails:          print(email)      print("\n")