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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 create_group(self, group):
 """Create and start a group. :param :class:`marathon.models.group.MarathonGroup` group: the group to create :returns: success :rtype: dict containing the version ID """

        data = group.to_json()
        response = self._do_request('POST', '/v2/groups', data=data)
        return response.json()