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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 field_value(self, value):
 """Validate against NodeType. """

        if not self.is_array:
            return self.field_type(value)

        if isinstance(value, (list, tuple, set)):
            return [self.field_type(item) for item in value]
        return self.field_type(value)