Three digit size N odometer

I want to generate all possible outputs of a list of size N that acts as a 3 digit odometer. For example, if N = 4, I want the following output:

0000 1000 2000 3000 0100 1100 ... 3332 3333.

Here is my code, any help is much appreciated!

odom = [0]*N  ## initialize odometer
print odom
while odom[N-1] <= 3:
    idx = 1
    odom[0] += 1
    if odom[0] > 3:
        while odom[idx] > 3:
            idx += 1
        for i in range(idx):
            odom[i] = 0
    print odom

def foo(n, digits = 4):
    if digits == 0:
        return ''
    msb, lsb = divmod(n, 4)
    return str(lsb) + foo(msb, digits - 1)

result = []
number_of_digits = 4
maxn = sum(3 * pow(number_of_digits,n) for n in range(number_of_digits))

for n in range(maxn + 1):
    result.append(foo(n, number_of_digits))

result = [foo(n, number_of_digits) for n in range(maxn + 1)]

foo_4 = functools.partial(foo, digits=4)
result = list(map(foo_4, range(maxn + 1)))