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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:

async def _body_callback(self, h11_connection):
        '''
        A callback func to be supplied if the user wants to do something
        directly with the response body's stream.
        '''
        # pylint: disable=not-callable
        while True:
            next_event = await self._recv_event(h11_connection)
            if isinstance(next_event, h11.Data):
                await self.callback(next_event.data)
            else:
                return next_event