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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _RemoveUsers(self, remove_users):
 """Deprovision Linux user accounts that do not appear in account metadata. Args: remove_users: list, the username strings of the Linux accounts to remove. """

    for username in remove_users:
      self.utils.RemoveUser(username)
      self.user_ssh_keys.pop(username, None)
    self.invalid_users -= set(remove_users)