what does the @ in python do

In Python , the ` @ ` symbol is used to define a decor ator function . A decor ator is a function that takes another function as an argument and returns a new function that has the behavior of the original function , but with some additional functionality or modifications . \n \n The decor ator function is called with the original function as an argument , and it returns a new function that can be used in the same way as the original function . The new function has the same name as the original function , but with the decor ator function ' s name app ended to it . \n \n For example , consider the following code : \n `` ` \n def gre et ( name ): \n print (" Hello , " + name + " ! ") \n \n @ gre et \n def say _ hello (): \n print (" Hello , world ! ") \n \n say _ hello () # Output : " Hello , world !" \n `` ` \n In this code , the ` gre et ` function is defined as a decor ator function that takes another function as an argument . The ` say _ hello ` function is then defined as a new function that is decorated with the ` gre et ` function . When the ` say _ hello ` function is called , it prints " Hello , world ! ", but the ` gre et ` function is called with the argument " world " before the ` say _ hello ` function is executed . This results in the output " Hello , world ! ". </s>