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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 svalue(self, value):
 """Change of serialized value. Nonify this value as well. :param str value: serialized value to use. """


        if value is not None:  # if value is not None
            self._value = None
            self._error = None

        self._svalue = value