An Israeli Air Force F-35 fighter jet flies during an aerial demonstration at a graduation ceremony for Israeli airforce pilots at the Hatzerim air base in southern Israel December 29, 2016. (Photo by Amir Cohen/Reuters)

Actors wrapped in blankets react at the set of the post-apocalyptic movie “Zombie Era” at an abandoned factory complex in Langfang, Hebei province, China December 16, 2016. (Photo by Damir Sagolj/Reuters)

Model Daisy Lowe presents a creation at the Katie Eary catwalk show during London Fashion Week Men's 2017 in London, Britain January 7, 2017. (Photo by Neil Hall/Reuters)

Drivers take part in a demolition derby organised by the Malta Motor Sports Association to raise funds for charity in Ta' Qali, outside Valletta, Malta, January 8, 2017. (Photo by Darrin Zammit Lupi/Reuters)

A man holds his umbrella during snowfall on the Areopagitou pedestrian street beneath the Acropolis hill during snowfall in Athens, Greece, January 10, 2017. (Photo by Alkis Konstantinidis/Reuters)

General view of a herbal store in Cairo, Egypt January 10, 2017. In an economic crisis that has led to a shortage of medicines, Egyptians are skipping trips to drug stores and instead turning to herbal remedies to treat every-day illnesses. (Photo by Mohamed Abd El Ghany/Reuters)

Children play with weapons during Children's Day celebration at a military facility in Bangkok, Thailand January 14, 2017. (Photo by Jorge Silva/Reuters)

Salvadoran clown Cosquilla poses for a picture during the VIII Central America Clown Convention in San Salvador, El Salvador, May 18, 2016. (Photo by Jose Cabezas/Reuters)