to run bob giveraise(method callpython looks up giveraise from bobby inheritance search passes bob to the located giveraise functionin the special self argument when you call employee giveraise(bob)you're just performing both steps yourself this description is technically the default case (python has additional method types we'll meet later)but it applies to the vast majority of the oop code written in the language to see how methods receive their subjectsthoughwe need to move on to some code coding class trees although we are speaking in the abstract herethere is tangible code behind all these ideasof course we construct trees and their objects with class statements and class callswhich we'll meet in more detail later in shorteach class statement generates new class object each time class is calledit generates new instance object instances are automatically linked to the classes from which they are created classes are automatically linked to their superclasses according to the way we list them in parentheses in class header linethe left-to-right order there gives the order in the tree to build the tree in figure - for examplewe would run python code of the following form like function definitionclasses are normally coded in module files and are run during an import ( 've omitted the guts of the class statements here for brevity)class class class ( )make class objects (ovalsi ( (make instance objects (rectangleslinked to their classes linked to superclasses (in this orderherewe build the three class objects by running three class statementsand make the two instance objects by calling the class twiceas though it were function the instances remember the class they were made fromand the class remembers its listed superclasses technicallythis example is using something called multiple inheritancewhich simply means that class has more than one superclass above it in the class tree-- useful technique when you wish to combine multiple tools in pythonif there is more than one superclass listed in parentheses in class statement (like ' here)their left-toright order gives the order in which those superclasses will be searched for attributes oop from , feet