code: def _get_url_scheme_regexes():
          
          output = sh("hg showconfig | grep '^schemes.'", shell=True).split('\n')
          log.debug(output)
          schemes = (
              l.split('.', 1)[1].split('=') for l in output if '=' in l)
          regexes = sorted(
              ((k, v, re.compile(v.replace('{1}', '(.*)')+'(.*)'))
                  for k, v in schemes),
              key=lambda x: (len(x[0]), x),
              reverse=True)
          return regexes
docs: Get configured mercurial schemes and convert them to regexes
  
          Returns:
              tuple: (scheme_name, scheme_value, compiled scheme_regex)