My Solution to Trello challenge

trello.py

""" Trello job challeng """
from itertools import product
import sys
import unittest

letters = "acdegilmnoprstuw"


def pyhash(s):
    """
    Int64 hash (String s) {
        Int64 h = 7
        String letters = "acdegilmnoprstuw"
        for(Int32 i = 0; i < s.length; i++) {
            h = (h * 37 + letters.indexOf(s[i]))
        }
        return h
    }
    """
    h = 7
    for i in range(len(s)):
        h = (h * 37 + letters.index(s[i]))
    return h


def bruteforce_pyhash_inverse(expected_result, length):
    for s in product(letters, repeat=length):
        s = ''.join(s)
        result = pyhash(s)
        if expected_result == result:
            return result


def pyhash_inverse(expected_result):
    """
    h = 7
    for i in range(len(s)):
        h = (h * 37) + letters.index(s[i])
    """
    s = []
    value = expected_result
    c = 0
    while value > 7:
        if value % 37 == 0:
            value = value // 37
            s.append(letters[c])
            c = 0
        else:
            c += 1
            value = value - 1

    s = ''.join(s[::-1])
    return s


class pyhashTestCase(unittest.TestCase):

    expected_result_7 = 680131659347
    test_s_7 = 'leepadg'
    test_l_7 = len(test_s_7)

    expected_result_3 = 354610
    test_s_3 = 'acd'
    test_l_3 = len(test_s_3)

    def test_pyhash(self):
        result = pyhash(self.test_s_7)
        self.assertEqual(result, self.expected_result_7)

    def test_bruteforce_pyhash_inverse(self):
        result = bruteforce_pyhash_inverse(self.expected_result_3,
                                           self.test_l_3)
        self.assertEqual(result, self.expected_result_3)

    def test_pyhash_inverse(self):
        result = pyhash_inverse(self.expected_result_7)
        self.assertEqual(len(result), self.test_l_7)
        self.assertEqual(result, self.test_s_7)


if __name__ == "__main__":
    if len(sys.argv) < 2:
        print("Usage: python trello_job.py <hash>")
        exit()
    value = int(sys.argv[1])
    result = pyhash_inverse(value)
    print(result)