text: from linkedlist.singlylinkedlist import Node
  from linkedlist.singlylinkedlist import SinglyLinkedList
  
  if __name__ == '__main__':
      node1 = Node(15)
      node2 = Node(8.2)
      node3 = Node(3)
  
      track = SinglyLinkedList()
  
      # Append
      print('append')
      track.append(56)
      track.append(40)
      track.append(1)
      track.append(30)
      track.append(20)
      track.append(10)
  
      for item in track:
          print(item)
  
      # Insert
      print('\ninsert')
      track.insert(5, 77)
  
      for item in track:
          print(item)
  
      # Index
      print('\nindex')
      search_item = 77
      print(f'{search_item} is at {track.index(search_item)}')
  
      # Remove
      print('\nremove')
      removed_item = 10
      track.remove(removed_item)
  
      for item in track:
          print(item)
  
      # Pop
      print('\npop')
      print(track.pop())
  
      # Reverse
      print('\nbefore reverse')
      for item in track:
          print(item)
  
      print('\nreverse')
      track.reverse()
  
      for item in track:
          print(item)
  
      # Sort
      print('\nsort')
      track.sort()
  
      for item in track:
          print(item)
  
      # Clear
      print('\nclear')
      track.clear()
  
      for item in track:
          print(item)
  
      print(f'total length : {track.size()}')
  