It's two photographs spliced together. Two images taken in quick succession with the camera mounted on a tripod. One with all of her in the image with her head in that position, then a second images is taken without her in the image at all. Then the two images are merged together. The one without her in the photo is on the left side of the lamp post, the one with her in it is on the right side of the lamp post. Very easy to achieve with minimal Photoshop skills. Like I say.... not very clever.