'surfacethe pygame surface object that stores the image of the squirrel which will be drawn to the screen 'movexhow many pixels per frame the squirrel moves horizontally negative integer is moving to the lefta positive to the right 'moveyhow many pixels per frame the squirrel moves vertically negative integer is moving upa positive moving down 'widththe width of the squirrel' imagein pixels 'heightthe height of the squirrel' imagein pixels 'bouncerepresents at what point in bounce the player is in means standing (no bounce)up to bouncerate (the completion of the bounce 'bounceratehow quickly the squirrel bounces lower number means quicker bounce 'bounceheighthow high (in pixelsthe squirrel bounces grass data structure keys 'grassimagean integer that refers to the index of the pygame surface object in grassimages used for this grass object ""the comments from lines to are in one largemulti-line string they describe the keys in the player squirrelenemy squirreland grass objects in pythona multi-line string value by itself works as multi-line comment the main(function def main() global fpsclockdisplaysurfbasicfontl_squir_imgr_squir_imggrassimages pygame init( fpsclock pygame time clock( pygame display set_icon(pygame image load('gameicon png') displaysurf pygame display set_mode((winwidthwinheight) pygame display set_caption('squirrel eat squirrel' basicfont pygame font font('freesansbold ttf' the first several lines of the main(function are the same setup code that we've seen in our previous game programs the pygame display set_icon(is pygame function that sets the icon in the window' title bar (just like pygame display set_caption(sets the caption text in the title barthe single argument to pygame display set_icon(is surface object of small image the ideal image size is pixelsalthough you can use other sized images the image will just be compressed into smaller size to be used as the window' icon