all the objects have the following keys in their dictionary value' '' 'and 'rectthe 'xand 'ykey' value give the coordinates of the top left of the object in game world coordinates these are different from pixel coordinates (which is what the 'rectkey' value tracksthe difference between game world and pixel coordinates will be explained when you learn about the concept of cameras in additionthe player squirrelenemy squirreland grass objects have other keys which are explained in large comment at the start of the source code source code to squirrel eat squirrel this source code can be downloaded from messageslook at the line number that is mentioned in the error message and check your code for any typos you can also copy and paste your code into the web form at book you will also need to download the following image files squirrel eat squirrel ( katamari damacy clone by al sweigart al@inventwithpython com creative commons by-nc-sa us import randomsystimemathpygame from pygame locals import fps frames per second to update the screen winwidth width of the program' windowin pixels winheight height in pixels half_winwidth int(winwidth half_winheight int(winheight grasscolor ( white ( red (