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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 from_json(cls, filename):
 """ Creates an experimental setup from a JSON file Parameters filename : str Absolute path to JSON file Returns ------- caspo.core.setup.Setup Created object instance """

        with open(filename) as fp:
            raw = json.load(fp)

        return cls(raw['stimuli'], raw['inhibitors'], raw['readouts'])