input: from typing import List
  
  def to_int_list(s: str) -> List[int]:
      """Convert a given string to a list of integers by splitting the string by commas
      and converting each split part to an integer.
  
      >>> to_int_list("1,2,3")
      [1, 2, 3]
      >>> to_int_list("10,20,30,40")
      [10, 20, 30, 40]
      """
output:     return [int(x) for x in s.split(',')]