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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 register(self, url, doc):
 """Register a DOI via the DataCite API. :param url: Specify the URL for the API. :param doc: Set metadata for DOI. :returns: `True` if is registered successfully. """

        try:
            self.pid.register()
            # Set metadata for DOI
            self.api.metadata_post(doc)
            # Mint DOI
            self.api.doi_post(self.pid.pid_value, url)
        except (DataCiteError, HttpError):
            logger.exception("Failed to register in DataCite",
                             extra=dict(pid=self.pid))
            raise
        logger.info("Successfully registered in DataCite",
                    extra=dict(pid=self.pid))
        return True