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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 download(self, image, url_field='url', suffix=None):
 """Download the binary data of an image attachment. :param image: an image attachment :type image: :class:`~groupy.api.attachments.Image` :param str url_field: the field of the image with the right URL :param str suffix: an optional URL suffix :return: binary image data :rtype: bytes """

        url = getattr(image, url_field)
        if suffix is not None:
            url = '.'.join(url, suffix)
        response = self.session.get(url)
        return response.content