docs: def update(self, process_list):
          """Update the AMP"""
          # Get the systemctl status
          logger.debug('{}: Update stats using service {}'.format(self.NAME, self.get('service_cmd')))
          try:
              res = check_output(self.get('service_cmd').split(), stderr=STDOUT).decode('utf-8')
          except OSError as e:
              logger.debug('{}: Error while executing service ({})'.format(self.NAME, e))
          else:
              status = {'running': 0, 'stopped': 0, 'upstart': 0}
              # For each line
              for r in res.split('\n'):
                  # Split per space .*
                  l = r.split()
                  if len(l) < 4:
                      continue
                  if l[1] == '+':
                      status['running'] += 1
                  elif l[1] == '-':
                      status['stopped'] += 1
                  elif l[1] == '?':
                      status['upstart'] += 1
              # Build the output (string) message
              output = 'Services\n'
              for k, v in iteritems(status):
                  output += '{}: {}\n'.format(k, v)
              self.set_result(output, separator=' ')
  
          return self.result()