python3实现短网址和数字相互转换的方法

import math
import decimal
def convert_to_code(num):
"""
将数字转换为代码
"""
def get_num(num, out=''):
num = decimal.Decimal(num)
codes = "abcdefghjkmnpqrstuvwxyz23456789ABCDEFGHJKMNPQRSTUVWXYZ"
if num > 53:
key = num % 54
num = math.floor(num / 54) - 1
return get_num(num, codes[int(key)] + out)
else:
return codes[int(num)] + out
return get_num(num)
def convert_to_num(code):
"""
将代码转为数字
"""
import math
codes = "abcdefghjkmnpqrstuvwxyz23456789ABCDEFGHJKMNPQRSTUVWXYZ"
num = 0
num = decimal.Decimal(num)
i = len(code)
for char in code:
i -= 1
pos = codes.find(char)
num += (54 ** i) * (pos + 1)
num -= 1
# 任意数的 0 次方等于1，所以需要减去
return int(num)