Think Python - Denison University

15.8. Glossary 151>>> hasattr(p, 'x')True>>> hasattr(p, 'z')FalseThe first argument can be any object; the second argument is a string that contains the name of theattribute.15.8 Glossaryclass: A user-defined type. A class definition creates anew classobject.class object: Anobjectthatcontainsinformationaboutauser-definedtype. Theclassobjectcanbeused tocreate instances of thetype.instance: An object that belongs toaclass.attribute: One of thenamed values associated withan object.embedded (object): Anobject that isstoredas an attributeof another object.shallow copy: To copy the contents of an object, including any references to embedded objects;implemented bythecopyfunction inthecopymodule.deep copy: To copy the contents of an object as well as any embedded objects, and any objectsembedded inthem, and soon; implemented bythedeepcopyfunction inthecopymodule.object diagram: A diagram that shows objects, their attributes, and thevalues of the attributes.15.9 ExercisesExercise15.4 World.py,whichispartofSwampy(seeChapter4),containsaclassdefinitionforauser-defined type calledWorld. You can import itlikethis:from World import WorldThis version of theimport statement imports theWorld class from theWorld module. The followingcodecreates aWorldobject and callsthemainloopmethod, which waits forthe user.world = World()world.mainloop()A window should appear with a title bar and an empty square. We will use this window to drawPoints, Rectangles and other shapes. Add the following lines before calling mainloop and run theprogram again.canvas = world.ca(width=500, height=500, background='white')bbox = [[-150,-100], [150, 100]]canvas.rectangle(bbox, outline='black', width=2, fill='green4')