input: from typing import List
  
  def positive_feedback_loop(iterations: int) -> List[str]:
      """
      This function generates a positive feedback loop for a given number of iterations,
      printing a message each time and adding a congratulatory message when the loop completes.
      
      >>> positive_feedback_loop(0)
      []
      >>> positive_feedback_loop(1)
      ["hello", "You've got it!"]
      >>> positive_feedback_loop(3)
      ["hello", "hello", "hello", "You've got it!"]
      """
      messages = []
      for i in range(iterations):
          messages.append("hello")
          i += 1
          if i == iterations:
              messages.append("You've got it!")
      return messages
output:     messages = []
      for i in range(iterations):
          messages.append("hello")
      if iterations > 0:
          messages.append("You've got it!")
      return messages