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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 root_manifest_id(self, root_manifest_id):
 """ Sets the root_manifest_id of this UpdateCampaignPutRequest. :param root_manifest_id: The root_manifest_id of this UpdateCampaignPutRequest. :type: str """

        if root_manifest_id is not None and len(root_manifest_id) > 32:
            raise ValueError("Invalid value for `root_manifest_id`, length must be less than or equal to `32`")

        self._root_manifest_id = root_manifest_id