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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_seeded_answers_simple(answers, options, algo):
 """ This validator checks if the answers includes all possible options Args: answers (str):
 the answers to be checked options (dict):
 all options that should exist in the answers algo (str):
 selection algorithm Returns: None if everything is good. Otherwise, the missing option error message. """

    seen_options = {}
    for answer in answers:
        if answer:
            key = options[answer['answer']].get('text')
            if options[answer['answer']].get('image_url'):
                key += options[answer['answer']].get('image_url')
            seen_options.setdefault(key, 0)
            seen_options[key] += 1

    missing_options = []
    index = 1
    for option in options:
        key = option.get('text') + option.get('image_url') if option.get('image_url') else option.get('text')
        if option.get('text') != 'n/a':
            if seen_options.get(key, 0) == 0:
                missing_options.append(_('Option ') + str(index))
            index += 1

    if missing_options:
        return {'seed_error': _('Missing option seed(s): ') + ', '.join(missing_options)}

    return None