the next is not needed in for methods without self argument that are called only through the class nameand never through an instance--such methods are run as simple functionswithout receiving an instance argument in xsuch calls are errors unless an instance is passed manually or the method is marked as being static (more on static methods in the next it' important to be aware of the differences in behavior in xbut bound methods are generally more important from practical perspective anyway because they pair together the instance and function in single objectthey can be treated as callables generically the next section demonstrates what this means in code for more visual illustration of unbound method treatment in python and xsee also the lister py example in the multiple inheritance section later in this its classes print the value of methods fetched from both instances and classesin both versions of python--as unbound methods in and simple functions in also note that this change is inherent in itselfnot the new-style class model it mandates bound methods and other callable objects as mentioned earlierbound methods can be processed as generic objectsjust like simple functions--they can be passed around program arbitrarily moreoverbecause bound methods combine both function and an instance in single packagethey can be treated like any other callable object and require no special syntax when invoked the followingfor examplestores four bound method objects in list and calls them later with normal call expressionsclass numberdef __init__(selfbase)self base base def double(self)return self base def triple(self)return self base number( number( number( double( class instance objects state methods acts [ doubley doubley triplez doublefor act in actsprint(act()list of bound methods calls are deferred call as though functions normal immediate calls methods are objectsbound or unbound