 The second statement, codice_5 re-binds the key sequence "C-x 2" to the new function.This can also be written using the feature called "advice", which allows the user to create wrappers around existing functions instead of defining their own.This has the advantage of not requiring keybindings to be changed and working wherever the original function is called, as well as being simpler to write but the disadvantage of making debugging more complicated.