7 kyu Multiplicative Persistence... What's special about 277777788888899?

"""
https://www.codewars.com/

Based on this Numberphile video: https://www.youtube.com/watch?v=Wim9WJeDTHQ

Multiply all the digits of a nonnegative integer n by each other, repeating with the product until a single digit is obtained. The number of steps required is known as the multiplicative persistence.

Create a function that calculates the individual results of each step, not including the original number, but including the single digit, and outputs the result as a list/array. If the input is a single digit, return an empty list/array.
Examples

per(1)  = []

per(10) = [0]
// 1*0 = 0

per(69) = [54, 20, 0]
// 6*9 = 54 --> 5*4 = 20 --> 2*0 = 0

per(277777788888899) = [4996238671872, 438939648, 4478976, 338688, 27648, 2688, 768, 336, 54, 20, 0]
// 2*7*7*7*7*7*7*8*8*8*8*8*8*9*9 = 4996238671872 --> 4*9*9*6*2*3*8*6*7*1*8*7*2 = 4478976 --> ...
"""

from functools import reduce

def per(n):
    if len(str(n)) == 1 or n == []:
        return []
        
    lst = []
    
    while n > 9:
        lst.append(reduce(int.__mul__, map(int, repr(n))))
        n = lst[-1]
        
    return lst