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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 in_words(amount, gender=None):
 """ Numeral in words @param amount: numeral @type amount: C{integer types}, C{float} or C{Decimal} @param gender: gender (MALE, FEMALE or NEUTER) @type gender: C{int} @return: in-words reprsentation of numeral @rtype: C{unicode} raise ValueError: when amount is negative """

    check_positive(amount)
    if isinstance(amount, Decimal) and amount.as_tuple()[2] == 0:
        # если целое,
        # т.е. Decimal.as_tuple -> (sign, digits tuple, exponent), exponent=0
        # то как целое
        amount = int(amount)
    if gender is None:
        args = (amount,)
    else:
        args = (amount, gender)
    # если целое
    if isinstance(amount, six.integer_types):
        return in_words_int(*args)
    # если дробное
    elif isinstance(amount, (float, Decimal)):
        return in_words_float(*args)
    # ни float, ни int, ни Decimal
    else:
        # до сюда не должно дойти
        raise TypeError(
            "amount should be number type (int, long, float, Decimal), got %s"
            % type(amount))