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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_auth_option(option, value):
 """Validate optional authentication parameters. """

    lower, value = validate(option, value)
    if lower not in _AUTH_OPTIONS:
        raise ConfigurationError('Unknown '
                                 'authentication option: %s' % (option,))
    return lower, value