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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 switch_to_aux_top_layer(self):
 """Context that construct cnn in the auxiliary arm."""

        if self.aux_top_layer is None:
            raise RuntimeError("Empty auxiliary top layer in the network.")
        saved_top_layer = self.top_layer
        saved_top_size = self.top_size
        self.top_layer = self.aux_top_layer
        self.top_size = self.aux_top_size
        yield
        self.aux_top_layer = self.top_layer
        self.aux_top_size = self.top_size
        self.top_layer = saved_top_layer
        self.top_size = saved_top_size