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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 params and return new influence."""

        for k, v in constants.items():
            self.params[k]['value'] *= v

        influence = self._calculate_influence(self.params['infl']['value'])
        return influence * self.params['lr']['value']