input: from typing import List
  
  def sum_of_digits(numbers: List[int]) -> int:
      """ Calculate the sum of digits for each number in the list and return their total sum.
      >>> sum_of_digits([6342, 123, 4567])
      46
      >>> sum_of_digits([987, 101, 2456])
      53
      """
      
output:     total_sum = 0
      for number in numbers:
          total_sum += sum(int(digit) for digit in str(number))
      return total_sum