def METHOD_NAME(entropy, rules, exclude=""):
    one_char_per_rules = ""
    for rule in rules:
        available_chars = _remove_excluded_chars(CHARACTER_SUBSETS[rule], exclude)
        value, entropy = _consume_entropy("", entropy, available_chars, 1)
        one_char_per_rules += value
    return [one_char_per_rules, entropy]