def _delete_record(self, identifier=None, rtype=None, name=None, content=None):
        """Delete an existing record.

        If the record doesn't exist, does nothing.
        """
        if not identifier:
            records = self._list_records(rtype, name, content)
            identifiers = [record["id"] for record in records]
        else:
            identifiers = [identifier]

        LOGGER.debug("delete_records: %s", identifiers)

        for record_id in identifiers:
            self._delete(
                "/v1/domains/{0}/records/{1}".format(
                    self.domain, record_id
                )
            )
            LOGGER.debug("delete_record: %s", record_id)

        LOGGER.debug("delete_record: %s", True)
        return True
Delete an existing record.

        If the record doesn't exist, does nothing.