gistfile1.py

# coding=utf-8

extense = [{ '0': ' ', '1': 'cento', '2': 'duzentos', '3': 'trezentos',
    '4': 'quatrocentos', '5': 'quinhentos ', '6': 'seiscentos', '7': 'setecentos',
    '8': 'oitocentos', '9': 'novecentos', '': ' ', ' ': ' '
}, {
    '0': ' ', '2': 'vinte', '3': 'trinta', '4': 'quarenta', '5': 'cinquenta',
    '6': 'sessenta', '7': 'setenta', '8': 'oitenta', '9': 'noventa',
    '': ' ', ' ': ' '
}, {
    '0': '', '1': 'um ', '2': 'dois ', '3': 'três ', '4': 'quatro',
    '5': 'cinco', '6': 'seis', '7': 'sete', '8': 'oito',
    '9': 'nove', '': ' ', ' ': ' '
}]

single_milhars = [ '',  'mil', 'milhão', 'bilhão', 'trilhão', 'quadrilhão' ]
milhars = [ '',  'mil', 'milhões', 'bilhões', 'trilhões', 'quadrilhões' ]

tens_twenty_lower = {
    '10': 'dez', '11': 'onze', '12': 'doze', '13': 'treze', '14': 'quatorze', '15': 'quinze',
    '16': 'dezeseis', '17': 'dezessete', '18': 'dezoito', '19': 'dezenove'
}

def split_in_houses(int_num):
    str_num = str(int_num)
    return list(str_num)

def complete_with_zeros(num_list):
    def mod_of_three(input_list):
        return len(split_in_houses(input_list)) % 3 is 0

    if not mod_of_three(num_list):
        not_complete = True
        while(not_complete):
            num_list.insert(0, '0')
            if mod_of_three(num_list):
                not_complete = False

    return num_list

def split_in_hundreds(num_list):
    digits = 3
    num_list = complete_with_zeros(num_list)
    new_list = [num_list[n:n+digits] for n in range(0, len(num_list), digits)]
    return new_list

def convert_in_tens(num_list):
    if num_list[1] is '0':
        return extense[2][num_list[2]]

    if num_list[1] is '1':
        tens = ''.join(num_list[1:])
        return tens_twenty_lower[tens]

    if int(num_list[1]) > 1:
        return "{} e {}".format(extense[1][num_list[1]], extense[2][num_list[2]])


def convert_hundred(hundred_num_list):
    full_hundred = hundred_num_list[0]
    if full_hundred is '0':
        return '' + convert_in_tens(hundred_num_list)
    elif ''.join(hundred_num_list) == '100':
        return 'cem'
    else:
        return "{} e {}".format(extense[0][full_hundred], convert_in_tens(hundred_num_list))

def convert_into_thousands(number_matrix):
    full_number = ''
    milhar_houses = len(number_matrix) - 1
    for index, hundred_num in enumerate(number_matrix):
        full_hundred = convert_hundred(hundred_num)
        if 'um' in full_hundred:
            full_number += "{} {} ".format(
                full_hundred,
                single_milhars[milhar_houses - index]
            )
            continue

        if full_hundred is not '':
            full_number += "{} {} ".format(
                full_hundred,
                milhars[milhar_houses - index]
            )

    return full_number

def convert(num):
    return convert_into_thousands(
        split_in_hundreds(
            split_in_houses(num)
        )
    )


if __name__ == '__main__':
    print('Digite um número')
    converted = False
    while not converted:
        try:
            print(
                convert(input())
            )
            converted = True
        except (SyntaxError, NameError):
            print('Digite somente números!')