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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 open(self):
 """Open a comm to the frontend if one isn't already open."""

        if self.comm is None:
            state, buffer_paths, buffers = _remove_buffers(self.get_state())

            args = dict(target_name='jupyter.widget',
                        data={'state': state, 'buffer_paths': buffer_paths},
                        buffers=buffers,
                        metadata={'version': __protocol_version__}
                        )
            if self._model_id is not None:
                args['comm_id'] = self._model_id

            self.comm = Comm(**args)