Find if a binary representation of an integer is a repeated (maybe incomplete) substring

binary_substring.py

def solution(n):
    d = [0] * 30
    l = 0
    while (n > 0):
        d[l] = n % 2
        n //= 2
        l += 1
    for p in range(1, l - 1):
        ok = True
        print(d[:l-p])
        for i in range(l - p):
            print(i, p, d[:i + p + 1])
            if d[i] != d[i + p]:
                ok = False
                break
        if ok and l - p > p:
            return p
    return -1


print(solution(955))