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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 modelshort(self):
 """ Short version of model name Dictionary defined in ``populations.py``:: SHORT_MODELNAMES = {'Planets':'pl', 'EBs':'eb', 'HEBs':'heb', 'BEBs':'beb', 'Blended Planets':'bpl', 'Specific BEB':'sbeb', 'Specific HEB':'sheb'} """

        try:
            name = SHORT_MODELNAMES[self.model]

            #add index if specific model is indexed
            if hasattr(self,'index'):
                name += '-{}'.format(self.index)

            return name

        except KeyError:
            raise KeyError('No short name for model: %s' % self.model)