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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 _build_model(self):
 """ Build model. """


        if "input_dim" not in self.settings:
            raise ValueError("Model parameter input_dim cannot be None.")

        self.linear = nn.Linear(
            self.settings["input_dim"], self.cardinality, self.settings["bias"]
        )