Migrants rush as they try to get on a train heading to the border with Serbia at the train station of Gevgelija, on the Macedonian-Greek border, on August 9, 2015. Non-EU Serbia's frontier with Hungary, which is in the bloc's passport-free Schengen zone, has become a major crossing point for the huge numbers of migrants entering the EU. (Photo by Dimitar Dilkoff/AFP Photo)

Olaf Niess catches swans on the river Alster near the town hall in Hamburg, Germany, 17 November 2015. The Alster swans are moving to their ice-free winter quarters on the Eppendorf Muehlenteich millpond until spring. (Photo by Bodo Marks/EPA)

Peasants in the re-taken Somme District work in the fields, circa 1916- 1917, in this Library of Congress handout photo. For women 100 years ago, opportunities to work beyond the home and take part in political life were very limited. As the 20th century progressed, hard-won progress included gradually improved voting rights, while the upheaval of war pushed doors ajar as women worked as part of the war effort. U.S. Library of Congress archive photos show women's workplaces ranging from a flour mill in England to a coal mine in Belgium or Lincoln Motor Co.'s welding department in Detroit. International Women's Day is celebrated on March 8. (Photo by Reuters/Bain Collection/Library of Congress)

Jyoti Amge, 25, who holds the Guinness World Records title for the “Shortest Living Woman”, shows her ink-marked finger after casting her vote at a polling station during the first phase of the general election in Nagpur, India, April 11, 2019. (Photo by Reuters/Stringer)

Ethnic Uyghur tourists guides wait to perform in a show for Chinese tourists on June 29, 2017 in the old town of Kashgar, in the far western Xinjiang province, China. Kashgar has long been considered the cultural heart of Xinjiang for the province's nearly 10 million Muslim Uyghurs. (Photo by Kevin Frayer/Getty Images)

A recruitment drive during the First World War at Trafalgar Square, London. (Photo by Central Press/Getty Images)

Protestors affiliated with the Occupy Wall Street movement block the entrance to the Iowa Democratic Party headquarters during a protest on December 29, 2011 in Des Moines, Iowa. Thirteen people were arrested during the protest. (Photo by Andrew Burton/Getty Images)

In this handout image provided by Carnival Australia, captain of the Queen Mary 2 Christopher Rynd poses on the desk of the Queen Mary 2 on February 8, 2012 in Perth, Australia. (Photo by James Morgan/Carnival Australia via Getty Images)