code: def extract_upgrade_scripts(self):
          
          link_pattern = '>\s*{0}\s*<'.format(self.pattern[1:-1])
          page = urllib.request.urlopen(self.upgrades_url).read()
          for mo in re.finditer(link_pattern, page):
              scriptname = mo.group(0)[1:-1].strip()
              yield self.parse_script_name(scriptname)
docs: Extract the OpenQuake upgrade scripts from the links in the GitHub page