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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 populate_obj(self, obj, keys=None):
 """Given the `obj` populate it using self.store items."""

        keys = keys or self.keys()
        for key in keys:
            key = key.upper()
            value = self.get(key, empty)
            if value is not empty:
                setattr(obj, key, value)