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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 health_indicator(self, health_indicator):
 """ Sets the health_indicator of this UpdateCampaign. An indication to the condition of the campaign. :param health_indicator: The health_indicator of this UpdateCampaign. :type: str """

        allowed_values = ["ok", "warning", "error"]
        if health_indicator not in allowed_values:
            raise ValueError(
                "Invalid value for `health_indicator` ({0}), must be one of {1}"
                .format(health_indicator, allowed_values)
            )

        self._health_indicator = health_indicator