如何在python中将数字转换为base 64？

我的代码没有失败，但是验证它是否正常工作的一个好方法是以几种不同的方式实现算法并进行比较：

# digits that will represent the base 64 number
base64Digits = ['0','1','2','3','4','5','6','7','8','9','a','b','c','d','e','f','g','h','i','j','k','l','m','n','o','p','q','r','s','t','u','v','w','x','y','z','A','B','C','D','E','F','G','H','I','J','K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z','-','!']

def base10to64converter(num):

    # Define the number of digits the result will have (limit of 2k)
    i = 1
    while i<2000:
        if num<64**i:
            digitNum = i
            i+=2000
        i+=1

    digits = []

    # calculate the number
    while digitNum > 0:
        digits.append(num // (64**(digitNum-1)))
        num %= (64**(digitNum-1))
        digitNum-=1

    result = ''
    j = 0

    # transform the digits stored in the array into an string
    while j < len(digits):
        result += base64Digits[digits[j]]
        j+=1

    return result

def alternate(n):
    if n < 0:
        raise ValueError('negative numbers not supported')
    base = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ-!'
    digits = []
    while n != 0:
        n,r = divmod(n,64)
        digits.append(base[r])
    if not digits:
        return '0'
    return ''.join(reversed(digits))

trials = [0,1,64,10**2000-1,10**2000]
for trial in trials:
    n = base10to64converter(trial)
    print(n)
    assert n == alternate(trial)

你的方法和我的方法在五次试验中返回相同的答案。