input: from typing import List
  
  
  def print_unique(my_list: List[float]) -> None:
      """Print the unique elements of a given list, one by one.
      >>> print_unique([1.0, 2.0, 3.0, 2.0, 3.0])
      1.0
      2.0
      3.0
      >>> print_unique([4.0, 5.0, 6.0, 7.0])
      4.0
      5.0
      6.0
      7.0
      """
output:     seen = set()
      for num in my_list:
          if num not in seen:
              print(num)
              seen.add(num)