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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 offsets(self, group=None):
 """Get internal consumer offset values Keyword Arguments: group: Either "fetch", "commit", "task_done", or "highwater". If no group specified, returns all groups. Returns: A copy of internal offsets struct """

        if not group:
            return {
                'fetch': self.offsets('fetch'),
                'commit': self.offsets('commit'),
                'task_done': self.offsets('task_done'),
                'highwater': self.offsets('highwater')
            }
        else:
            return dict(deepcopy(getattr(self._offsets, group)))