input: Write a function to convert a given string to a list of integers by splitting the string based on commas. If the input string is empty, return an empty list.
  def to_int_list(s):
      return [int(x) for x in s.split(',')] if s else []
  
  assert to_int_list("1,2,3,4,5")==[1, 2, 3, 4, 5]
  assert to_int_list("10,20,30")==[10, 20, 30]
  assert to_int_list("")==[]
  assert to_int_list("5,10,15,20")==[5, 10, 15, 20]
output: def to_int_list(s):
      return [int(x) for x in s.split(',')] if s else []