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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 update_model_params(self, **params):
 r"""Update given model parameter if they are set to specific values"""

        for key, value in params.items():
            if not hasattr(self, key):
                setattr(self, key, value)  # set parameter for the first time.
            elif getattr(self, key) is None:
                setattr(self, key, value)  # update because this parameter is still None.
            elif value is not None:
                setattr(self, key, value)