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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 register_predictor(cls, name):
 """Register method to keep list of predictors."""

        def decorator(subclass):
            """Register as decorator function."""
            cls._predictors[name.lower()] = subclass
            subclass.name = name.lower()
            return subclass
        return decorator