A visitor walks on a giant chalk artwork called “Wasting Time” at the Chalk Urban Arts Festival in Sydney on October 25, 2014. The picture is the biggest 3-D artwork created in Australia by two artists, Leon Keer from Holland and Jenny McCracken from Australia. (Photo by Peter Parks/AFP Photo)

In this photograph taken on Thursday, November 20, 2014, bud tenders Maxwell Bradford, back left, and Emma Attolini display buds in the shape of Christmas trees that are on sale for the holiday season in a recreational marijuana shop in northwest Denver. The nascent marijuana industry in Colorado is targeting holiday shoppers with special deals much like traditional retailers offer. (Photo by David Zalubowski/AP Photo)

People take part in the Classic Ride Rally in downtown Valencia, eastern Spain, 23 November 2014. Some hundred people on classic bikes from the 20's to the 70's participated in the rally. (Photo by Kai Foersterling/EPA)

In this December 18, 2013 photo released by Six Flags Discovery Kingdom, 32 men dressed as Santa Claus ride the 150-foot tall SkyScreamer tower swing ride at Six Flags Discovery Kingdom in Vallejo, Calif. (Photo by Jason Quintos/AP Photo/Six Flags Discovery Kingdom)

“Falling Back To Earth” promises to be both spectacular and meditative, and presents a beautiful, thought-provoking vision of our relationship with the earth and with each other. (Photo by Dave Hunt/EPA)

Jesse Tyler Ferguson photobombs Miranda Kerr and Orlando Bloom at the 2013 Vanity Fair Oscar party. (Photo by Jon Kopaloff/FilmMagic)

Zhao Qiang walks across a street in Shenyang, Liaoning province, April 14, 2014. Zhao, a community officer of the China Disabled Persons' Federation, was diagnosed with multiple when he was two, with the resulting tumour affecting the growth of his left leg, his grandmother told local media, citing a doctor's diagnosis. His uncle modified his shoes, fitting them with stools, to allow Zhao to stand and walk. (Photo by Reuters/Stringer)

A person tries to extinguish flames as sparks fly during a wild forest fire in Valparaiso, Chile, Sunday April 13, 2014. Authorities say the fires have destroyed hundreds of homes, forced the evacuation of thousands and claimed the lives of at least seven people. (Photo by Luis Hidalgo/AP Photo)