input: Write a function that completes the task described in the given instruction and modifies the python program to include a positive feedback loop. The function should take a list of integers representing the lines of the original program, and return a modified list of integers representing the lines of the modified program.
  assert positive_feedback_loop([['for i in range(10):', '    print("hello")']]) == ['for i in range(10):', '    print("hello")', '    i += 1', '    if i == 10:', '        print("You\'ve got it!")']
  assert positive_feedback_loop([]) == []
  assert positive_feedback_loop([['print("hello")']]) == [['print("hello")']]
  assert positive_feedback_loop([['for i in range(5):', '    print("hi")']]) == ['for i in range(5):', '    print("hi")', '    i += 1', '    if i == 5:', '        print("You\'ve got it!")']
output: def positive_feedback_loop(lines):
      if not lines:
          return lines
      modified_lines = []
      for line in lines:
          modified_lines.append(line)
          if 'for i in range(' in line:
              modified_lines.append('    i += 1')
              modified_lines.append('    if i == 10:')
              modified_lines.append("        print(\"You've got it!\")")
      return modified_lines