Generate an image  of a playful  boy, approximately  6- 8 years old , wearing a  pink underwear with  blue star designs  as a makeshift  mask, covering  his nose  and mouth,  while holding a  bright green toy  gun with yellow accents , set  against a warm  and sunny backyard  or playground environment  with a shallow  depth of field , emphasizing the  boy's creative  and imaginative play time.