pydraw wxpython example application the final class is the pydrawapp class that extends the wx app class object relationships howeverthe inheritance hierarchy is only part of the story for any object oriented application the following figure illustrates how the objects relate to one another within the working application the pydrawframe is responsible for setting up the controller and the drawingpanel the pydrawcontroller is responsible for handling menu and tool bar user interactions this separates graphical elements from the behaviour triggered by the user