input: def to_int_list(s: str) -> List[int]:
      """Convert a given string to a list of integers, where each integer is separated by a comma.
      >>> to_int_list("1,2,3,4")
      [1, 2, 3, 4]
      >>> to_int_list("10,-5,0,100")
      [10, -5, 0, 100]
      """
output:     return [int(num) for num in s.split(',')]