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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 get_value(self, index):

 """Return current value"""

        if index.column() == 0:
            return self.keys[ index.row() ]
        elif index.column() == 1:
            return self.types[ index.row() ]
        elif index.column() == 2:
            return self.sizes[ index.row() ]
        else:
            return self._data[ self.keys[index.row()] ]