Draws the current frame of the animation

        Should be called in every frame.

def draw(self):
        """Draws the current frame of the animation

        Should be called in every frame.

        """
        # Assumes that self.index has been set earlier (typically in update method)
        # it is used as the index of the current image/endTime/loc
        theImage = self.imagesList[self.index]  # choose the image to show

        if theImage is None:  # if there is no image to show
            return

        if self.visible:
            theOffset = self.offsetsList[self.index]
            theLoc = ((self.loc[0] + theOffset[0]), (self.loc[1] + theOffset[1]))
            self.window.blit(theImage, theLoc)