code: def _UpdateUsers(self, update_users):
      
      for user, ssh_keys in update_users.items():
        if not user or user in self.invalid_users:
          continue
        configured_keys = self.user_ssh_keys.get(user, [])
        if set(ssh_keys) != set(configured_keys):
          if not self.utils.UpdateUser(user, ssh_keys):
            self.invalid_users.add(user)
          else:
            self.user_ssh_keys[user] = ssh_keys[:]
docs: Provision and update Linux user accounts based on account metadata.
  
      Args:
        update_users: dict, authorized users mapped to their public SSH keys.