Multiplicative Persistence Comment

#!/usr/bin/python3
from functools import reduce as rd


# a comment on https://youtu.be/Wim9WJeDTHQ

def mul(a: int, b: int) -> int:
    return a * b


digits = lambda _t: (int(_i) for _i in str(_t))


def multiplicative_persistence(x: int, show: bool = True) -> int:
    tmp: int = x
    count: int = 1
    while True:
        tmp_exp: [int] = tuple(digits(tmp))
        if show:
            print(f'#{count} is {tmp} (length {len(tmp_exp)})')
        if len(tmp_exp) == 1:
            break
        try:
            tmp = rd(mul, tmp_exp)
        except OverflowError:
            if show:
                print('Crash')
                break
            else:
                raise
        count += 1
    return count


mp = multiplicative_persistence


def dsum(_d: [int]) -> int:
    l: int = len(_d) - 1
    return sum(v * 10 ** (l - i) for i, v in enumerate(_d))