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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 add(self, *resources):
 """ Apply the tag to one or more resources :param resources: one or more `Resource` objects to which tags can be applied :return: `None` :raises DOAPIError: if the API endpoint replies with an error """

        self.doapi_manager.request(self.url + '/resources', method='POST',
                                   data={"resources": _to_taggable(resources)})