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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 create(cls, name, ncpus=None):
 """Create a Moap instance based on the predictor name. Parameters name : str ncpus : int, optional Number of threads. Default is the number specified in the config. Returns ------- moap : Moap instance moap instance. """

        try:
            return cls._predictors[name.lower()](ncpus=ncpus)
        except KeyError:
            raise Exception("Unknown class")