input: Write a function to add a given mark to each value in a list of marks. If the marks list is empty, return an empty list.
  
  def add_marks(marks, mark):
      return [m + mark for m in marks]
  
  assert add_marks([87, 56, 99, 54], 4) == [91, 60, 103, 58]
  assert add_marks([], 4) == []
output: def add_marks(marks, mark):
      return [m + mark for m in marks]