input: from typing import List
  
  
  def prime_factors(n: int) -> List[int]:
      """ Return an ordered list of prime factors of the given integer. 
      Each factor should appear as many times as it is present in the factorization.
      The input number must equal the product of all these factors.
      >>> prime_factors(8)
      [2, 2, 2]
      >>> prime_factors(25)
      [5, 5]
      >>> prime_factors(70)
      [2, 5, 7]
      
output:     factors = []
      divisor = 2
      while n >= 2:
          while n % divisor == 0:
              factors.append(divisor)
              n //= divisor
          divisor += 1
      return factors