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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 _set_parameters(self, parameters):
 """Add parameters to the model and initialize with given values."""

        for theta in self.variables['theta']:
            val = 1.0
            # TODO: improve approach for initializing parameters.
            if parameters is not None:
                if theta.name in parameters:
                    val = parameters[theta.name]
            # Add parameter.
            
            self.link_parameters(Param(theta.name, val, None))