def download(self, attachment_id, destination):
        """
        Download an attachment from Zendesk.

        :param attachment_id: id of the attachment to download
        :param destination: destination path. If a directory, the file will be placed in the directory with
                            the filename from the Attachment object.
        :return: the path the file was written to
        """
        attachment = self(id=attachment_id)
        if os.path.isdir(destination):
            destination = os.path.join(destination, attachment.file_name)
        return self._download_file(attachment.content_url, destination)
Download an attachment from Zendesk.

        :param attachment_id: id of the attachment to download
        :param destination: destination path. If a directory, the file will be placed in the directory with
                            the filename from the Attachment object.
        :return: the path the file was written to