input: Write a function to design a positive feedback loop for a given Python program that prints "hello" 10 times. The function should modify the program such that after each "hello" is printed, a counter increments, and if the counter reaches 10, it prints "You've got it!" instead. If the input program is empty, the function should return the original input without any changes.
  
  def add_positive_feedback_loop(program):
      if not program.strip():
          return program
      loop_start = program.find("for")
      loop_end = program.find(":", loop_start) + 1
      loop_body = program[loop_start:loop_end]
      new_body = loop_body + "\n    i += 1\n    if i == 10:\n        print(\"You've got it!\")\n"
      return program[:loop_start] + new_body + program[loop_end:]
  
  assert add_positive_feedback_loop("for i in range(10):\n    print(\"hello\")") == "for i in range(10):\n    print(\"hello\")\n    i += 1\n    if i == 10:\n        print(\"You've got it!\")\n"
  assert add_positive_feedback_loop("") == ""
  assert add_positive_feedback_loop("for i in range(5):\n    print(\"hi\")") == "for i in range(5):\n    print(\"hi\")\n    i += 1\n    if i == 10:\n        print(\"You've got it!\")\n"
output: def add_positive_feedback_loop(program):
      if not program.strip():
          return program
      loop_start = program.find("for")
      loop_end = program.find(":", loop_start) + 1
      loop_body = program[loop_start:loop_end]
      new_body = loop_body + "\n    i += 1\n    if i == 10:\n        print(\"You've got it!\")\n"
      return program[:loop_start] + new_body + program[loop_end:]