要求是
def count_digits():
(str) -> int
例如
>>>count_digits(123abc456)
6
感激不尽
Type "help", "copyright", "credits" or "license" for more information.
>>> from string import digits
>>> def countdigit(s):
... return len(filter(lambda x: x in digits, s))
...
>>> countdigit('123abc456')
6
>>> import re
>>> digitpatt = re.compile('\d')
>>> def countdigits(s):
... return len(digitpatt.findall(s))
...
>>> countdigit('123abc456')
6
>>>