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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 fit_from_image(self, data, voxelsize, seeds, unique_cls):
 """ This Method allows computes feature vector and train model. :cls: list of index number of requested classes in seeds """

        fvs, clsselected = self.features_from_image(data, voxelsize, seeds, unique_cls)
        self.fit(fvs, clsselected)