Trello application puzzle in Python

trello.py

letters = "acdegilmnoprstuw"

def hash(s):
    h = 7
    for char in s:
        h = h * 37 + letters.index(char)
    return h

target = 910897038977002.0
current = target
t = ""
while len(t) < 9:
    for i, char in enumerate(letters):
        if (current - i) % 37 == 0:
            t += char
            current = (current - i) / 37
            break

t = t[::-1]

print(t, hash(t))
assert target == hash(t), 'hash("%s") == %d' % (t, hash(t))

trello2.py

# another, better solution

letters = "acdegilmnoprstuw"

def hash(s):
    h = 7
    for char in s:
        h = h * 37 + letters.index(char)
    return h

target = 956446786872726
current = target
t = ""
while len(t) < 9:
    i = current % 37
    t += letters[i]
    current = (current - i) / 37

t = t[::-1]

print(t, hash(t))
assert target == hash(t), 'hash("%s") == %d' % (t, hash(t))