def _process_configuration(comments):
    """Extract sampling information."""
    num_samples = None
    num_warmup = None
    save_warmup = None
    for comment in comments:
        comment = comment.strip('#').strip()
        if comment.startswith('num_samples'):
            num_samples = int(comment.strip('num_samples = ').strip(
                '(Default)'))
        elif comment.startswith('num_warmup'):
            num_warmup = int(comment.strip('num_warmup = ').strip('(Default)'))
        elif comment.startswith('save_warmup'):
            save_warmup = bool(int(comment.strip('save_warmup = ').strip(
                '(Default)')))
        elif comment.startswith('thin'):
            thin = int(comment.strip('thin = ').strip('(Default)'))
    return {'num_samples': num_samples, 'num_warmup': num_warmup,
        'save_warmup': save_warmup, 'thin': thin}
