{
    class_path: 'ExactMatch',
    init_args: {
        lm_output_processor: [
            { class_path: 'StringLower' },
            { class_path: 'RegexExtractor', init_args: { pattern: '"?answer"?:\\s*"?([a-z])"?'}}
        ],
        reference_processor: [
            { class_path: 'StringLower' },
        ],
    }
}