python怎么找出所有的数字？

# -*- coding: cp936 -*-

import re

string="A1.45，b5，6.45，8.82"

print re.findall(r"\d+\.?\d*",string)

# ['1.45', '5', '6.45', '8.82']

s = "dede323frf54de23"

l = len(s)

numbers = []

i = 0

while i < l:

    num = ''

    symbol = s[i]

    while '0' <= symbol <= '9': # symbol.isdigit()

        num += symbol

        i += 1

        if i < l:

            symbol = s[i]

        else:

            break

    i += 1

    if num != '':

        numbers.append(int(num))

print(numbers)