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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 enter_maintenance_mode(self):
 """ Put the host in maintenance mode. @return: Reference to the completed command. @since: API v2 """

    cmd = self._cmd('enterMaintenanceMode')
    if cmd.success:
      self._update(get_host(self._get_resource_root(), self.hostId))
    return cmd