in this short piece of codey is reference to the str object created from the string literal the variable is reference to an object that is created by using the object that refers to in generalwhen we want to create an object based on other object values we write the followingvariable type(other_object_valuesthe type is any type or class name in pythonlike intfloatstr or any other type the other_object_values is comma-separated sequence of references to other objects that are needed by the class or type to create an instance ( an objectof that type here are some examples of creating objects from non-literal values float(' ' str(zu list(wthis results in the list [' ''' ' calling methods on objects objects are useful because they allow us to collect related information and group them with behavior that act on this data these behaviors are called methods in python there are two kinds of methods in any object-oriented languagemutator and accessor methods accessor methods access the current state of an object but don' change the object accessor methods return new object references when called 'how are youy upper(print(yherethe method upper is called on the object that refers to the upper accessor method returns new objecta str objectthat is an upper-cased version of the original string note that is not changed by calling the upper method on it the upper method is an accessor method there are many accessor methods available on the str type which you can learn about in the appendices some methods are mutator methods these methods actually change the existing object one good example of this is the reverse method on the list type mylist [ mylist reverse(print(mylistthis prints [ to the screen the reverse method mutates the existing objectin this case the list that mylist refers to once calleda mutator method can' be undone the change or mutation is permanent until mutated again by some other mutator method all classes contain accessor methods without accessor methodsthe class would be pretty uninteresting we use accessor methods to retrieve value that is stored in an object or to retrieve value that depends on the value stored in an object this copy belongs to 'acha