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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 validate_none_of(values):
 """ Validate that a field is not in one of the given values. :param values: Iterable of invalid values. :raises: ``ValidationError('none_of')`` """

    def none_of_validator(field, data):
        options = values
        if callable(options):
            options = options()
        if field.value in options:
            raise ValidationError('none_of', choices=str.join(', ', options))
    return none_of_validator