This is an example of personification. Personification is giving human qualities to non-human things. In this case, the tinfoil is "winking" at them in the sun. This gives the impression tinfoil has eyes and a personality, as well as the capability to interact with people. But it literally means tthat he sun is glinting off the reflective surface of the tinfoil and catching their eye.
its personification cause she is sayin that the tinfoil is winking