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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 value(self):
 """Return the DATA_OBJECT stored value."""

        dtype = lib.get_data_type(self._data)
        dvalue = lib.get_data_value(self._data)

        if dvalue == ffi.NULL:
            return None

        return self.python_value(dtype, dvalue)