Labourers pour molten iron into a container at a foundry in Xiangfan, Hubei province in this July 2, 2010 file photo. Iron ore is enjoying its biggest rally in years, outpacing copper and oil so far in 2016, but still weak forward prices show it may be tough to stretch the bullish outlook. Improving steel prices in top market China are helping fuel iron ore's climb as producers gear up for a seasonal uptick in demand. Yet there is no shortage of doubters who see gains in the bulk commodity as fleeting given a large glut and challenges for China's economy. (Photo by Reuters/Stringer)

People participate in a pillow fight to mark International Pillow Fight Day in the Heroes' Square, in central Budapest, Hungary, Saturday, April 2, 2016. The Pillow Fight Day attracts tens of thousands people in more than 100 cities all over the World each year. ((Photo by Zoltan Balogh/MTI via AP Photo)

French firemen wearing chemical protective suits take part in a mock chemical attack exercise at the Geoffroy Guichard stadium in Saint-Etienne, France, April 4, 2016 in preparation of security measures for the UEFA 2016 European Championship. (Photo by Robert Pratta/Reuters)

People follow king penguins exploring their outdoor pen, during a so-called “penguin parade”, when the animals walk outside their enclosure and the visitors can walk behind them, at Zurich's Zoo in Zurich, Switzerland January 28, 2017. (Photo by Arnd Wiegmann/Reuters)

Danila Shmelev, an artist from Moscow, Russia, works on a 3-D picture in Dubai, United Arab Emirates, Monday, February 27, 2017. Artists who focus on 3-D pictures have gathered in Dubai for the Dubai Canvas 3-D Art Festival, which runs from March 1 through March 7. (Photo by Jon Gambrell/AP Photo)

Contestant Nathalie De Oliveira of Brazil prepares backstage before the final show of the Miss International Queen 2016 transgender/transsexual beauty pageant in Pattaya, Thailand, March 10, 2017. Thai contestant Jiratchaya Sirimongkolnawin was crowned Miss International Queen 2016. The 2016 show was postponed from November last year due to Thailand's mourning period of its late King Bhumibol Adulyadej who died at age 88 on October 13, 2016. (Photo by Athit Perawongmetha/Reuters)

Brittnai of El Paso, Texas, USA, performs in the Professional Division Competition during the 5th Annual US Pole Dance Championship on April 1, 2017 at the Symphony Space Theater in New York City. (Photo by Timothy A. Clary/AFP Photo)

Festival goers dance during Glastonbury Festival at Worthy Farm, near Pilton, Somerset, Britain, 23 June 2017. The outdoor festival runs from 21 to 25 June. (Photo by Nigel Roddis/EPA)