input: Write a function to design a positive feedback loop for the given input code. The function should modify the input code to include a condition that prints a positive feedback message "You've got it!" when the loop completes. If the input code is empty, the function should return the same empty code.
  assert positive_feedback("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 positive_feedback("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 positive_feedback("")==""
  assert positive_feedback("for i in range(20):")=="for i in range(20):\n    i += 1\n    if i == 20:\n        print(\"You've got it!\")"
  assert positive_feedback("for i in range(3):\n    print(i)")=="for i in range(3):\n    print(i)\n    i += 1\n    if i == 3:\n        print(\"You've got it!\")"
output: def positive_feedback(code):
      if not code:
          return code
      lines = code.split('\n')
      loop_line = lines[0]
      loop_range = loop_line.split('(')[1].split(')')[0]
      if ':' not in loop_range:
          loop_range = loop_range.split(':')[0]
      loop_range = int(loop_range)
      new_lines = lines + [f"    i += 1", f"    if i == {loop_range}:\n        print(\"You've got it!\")"]
      return '\n'.join(new_lines)