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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 set_value(self, model, value):
 """Set field's value. :param DomainModel model: :param object value: """

        if value is None and self.required:
            raise AttributeError("This field is required.")

        if value is not None:
            value = self._converter(value)

        setattr(model, self.storage_name, value)