code: def check_credentials(client):
      
      pid, uid, gid = get_peercred(client)
  
      euid = os.geteuid()
      client_name = "PID:%s UID:%s GID:%s" % (pid, uid, gid)
      if uid not in (0, euid):
          raise SuspiciousClient("Can't accept client with %s. It doesn't match the current EUID:%s or ROOT." % (
              client_name, euid
          ))
  
      _LOG("Accepted connection on fd:%s from %s" % (client.fileno(), client_name))
      return pid, uid, gid
docs: Checks credentials for given socket.