old_contents: List=[11,22,33,44,55,66,77,88]
  List.append(100)
  print(List)
  
  List[3:3]=["h","e","l","o"]
  print(List)
  
new_contents: List=[11,22,33,44,55,66,77,88]
  
  #append element 
  List.append(100)
  print(List)
  
  #add list from index
  List[3:3]=["h","e","l","o"]
  print(List)
  
  #insert elemnt at index
  List.insert(1,"hello")
  print(List)
  
subject: Update 3list_append.py