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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_params(self, constants):
 """Update the params."""

        constants = np.max(np.min(constants, 1))
        self.params['r']['value'] = max([self.params['r']['value'],
                                         constants])
        epsilon = constants / self.params['r']['value']
        influence = self._calculate_influence(epsilon)
        # Account for learning rate
        return influence * epsilon