input: Write a function to add a positive feedback loop to a given Python program. The input is a simple loop that prints "hello" ten times. The function should modify the loop so that after the loop completes, it prints "You've got it!" if i reaches 10. The function should return the modified Python code as a string.
  
  assert add_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!')"
  assert add_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!')"
  assert add_feedback_loop("") == ""
  assert add_feedback_loop("for i in range(20):\n    print('world')") == "for i in range(20):\n    print('world')\n    i += 1\n    if i == 10:\n        print('You've got it!')"
output: def add_feedback_loop(code):
      if not code:
          return code
      modified_code = code.rstrip()
      modified_code += "\n    i += 1\n    if i == 10:\n        print('You've got it!')"
      return modified_code