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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 columns_classes(self):
        '''returns columns count'''
        md = 12 / self.objects_per_row
        sm = None
        if self.objects_per_row > 2:
            sm = 12 / (self.objects_per_row / 2)
        return md, (sm or md), 12