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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 show_item_dict(self, item):
 """Returns a json-able dict for show"""

        d = {}
        for col in self.show_columns:
            v = getattr(item, col)
            if not isinstance(v, (int, float, string_types)):
                v = str(v)
            d[col] = v
        return d