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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 update_power_state(self, id_or_uri, power_state):
 """ Sets the power state of the specified power delivery device. The device must be an HP Intelligent Outlet. Args: id_or_uri: Can be either the power device id or the uri power_state: {"powerState":"On|Off"} Returns: str: The power state """

        uri = self._client.build_uri(id_or_uri) + "/powerState"
        return self._client.update(power_state, uri)