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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):
 """ A tuple of values. This attribute can be set with any iterable; the iterable is then evaluated into a tuple and stored at the bound field. Whenever values are written to this attribute, they are passed through the :meth:`~.AbstractCDataType.coerce` method of the :attr:`~.AbstractField.type_` of the field. To revert the :attr:`value` to its default, use the ``del`` operator. """

        try:
            return self._value
        except AttributeError:
            self.value = self._field.default()
            return self._value