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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 export(self, path, variables_saver=None):
 """Exports to SavedModel directory. Args: path: path where to export the SavedModel to. variables_saver: lambda that receives a directory path where to export checkpoints of variables. """

    # Operate on a copy of self._proto since it needs to be modified.
    proto = saved_model_pb2.SavedModel()
    proto.CopyFrom(self._proto)
    assets_map = _make_assets_key_collection(proto, path)

    self._save_all_assets(path, assets_map)
    self._save_variables(path, variables_saver)
    self._save_proto(path, proto)