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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 get(self, id):
 """Get a single group by ID. :param str id: a group ID :return: a group :rtype: :class:`~groupy.api.groups.Group` """

        url = utils.urljoin(self.url, id)
        response = self.session.get(url)
        return Group(self, **response.data)