input: Write a function to design a positive feedback loop for the given Python program. The function should modify the original program to include a feedback mechanism that increments the loop variable and prints a positive message when the loop completes. If the given program is empty, the function should return the original program without any modifications.
  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("") == ""
  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 == 5:\\n        print(\\"You've got it!\\")"
  assert add_feedback_loop("for i in range(3):\\n    print(\\"hello world\\")") == "for i in range(3):\\n    print(\\"hello world\\")\\n    i += 1\\n    if i == 3:\\n        print(\\"You've got it!\\")"
output: def add_feedback_loop(program):
      if not program:
          return program
      lines = program.splitlines()
      loop_line = lines[0]
      loop_var = loop_line.split()[1]
      loop_end = loop_line.split('range(')[1].split(')')[0]
      feedback_lines = [
          f"    {loop_var} += 1",
          f"    if {loop_var} == {loop_end}:",
          '        print("You\'ve got it!")'
      ]
      return '\n'.join(lines + feedback_lines)