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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 raw_dataset(self):
 """ Generate a raw dataset based on the queryset and the specified fields. """

        dataset = {}
        queryset = self.queryset.values_list(*(['pk'] + self.fields))
        if self.limit:
            queryset = queryset[:self.limit]
        for item in queryset:
            item = list(item)
            item_pk = item.pop(0)
            datas = ' '.join(map(six.text_type, item))
            dataset[item_pk] = self.raw_clean(datas)
        return dataset