A sign is seen outside a newly opened coronavirus (COVID-19) clearing-up centre in Berlin, Germany March 9, 2020. REUTERS/Michele Tantussi 

A sign is seen outside a newly opened coronavirus (COVID-19) clearing-up centre in Berlin, Germany March 9, 2020. REUTERS/Michele Tantussi 

A sign indicates the way to the city of Puerto Williams, Chile May 16, 2019. Picture taken May 16, 2019. REUTERS/Jorge Vega 

An Israeli soldier stands next to signs pointing out distances to different cities, on Mount Bental, an observation point in the Israeli-occupied Golan Heights that overlooks the Syrian side of the Quneitra crossing, Israel May 10, 2018. REUTERS/Ronen Zvulun TPX IMAGES OF THE DAY 

Pigeons are seen perched on windows in the old city of Damascus, Syria April 17, 2018. REUTERS/Ali Hashisho TPX IMAGES OF THE DAY 

A sign marks part of a route used to test a driverless electric shuttle at the University of Michigan in Ann Arbor, Michigan, U.S. March 7, 2018. Picture taken March 7, 2018. REUTERS/Paul Lienert 

Fish are seen for sale at "Wildwoods" in Crews Hill, Enfield, Britain December 4, 2017. REUTERS/ Tom Jacobs 

An X-Ray Department sign is pictured in a hospital in Philadelphia , Pennsylvania, U.S. May 30, 2017. Picture taken May 30, 2017. REUTERS/Carlo Allegri 

A road sign showing the direction of a hospital with an Accident and Emergency department is seen in west London, Britain, January 7, 2017. REUTERS/Toby Melville 

A list of the best-performing stocks on the ASX200 index are shown on an electronic board at the Australian Stock Exchange (ASX) in Sydney on the first full day of trading following Donald Trump's win in the U.S. presidential election, November 10, 2016. REUTERS/Jason Reed TPX IMAGES OF THE DAY

A piece of tape with Miami written on it and a direction where to go is pictured as U.S. Republican presidential nominee Donald Trump holds a campaign event in Miami, Florida U.S. November 2, 2016. REUTERS/Carlo Allegri 

U.S. Democratic presidential nominee Hillary Clinton's campaign plane is seen in White Plains, New York, U.S. October 11, 2016. REUTERS/Lucy Nicholson 

U.S. Democratic presidential nominee Hillary Clinton's campaign plane flies over Manhattan, New York, U.S. October 11, 2016. REUTERS/Lucy Nicholson 

A Secret Service agent keeps watch in a hallway as U.S. President Barack Obama casts his vote for president in early voting at the Cook County Office Building in Chicago, Illinois, U.S. October 7, 2016. REUTERS/Jonathan Ernst 

People attend prayers for the Muslim holiday of Eid Al-Adha on a street in Jakarta, Indonesia September 12, 2016. REUTERS/Darren Whiteside 

People attend prayers for the Muslim holiday of Eid Al-Adha on a street in Jakarta , Indonesia September 12, 2016. REUTERS/Darren Whiteside TPX IMAGES OF THE DAY

Road signs indicate the way to the channel tunnel of the Rocade road in Calais, France, September 6, 2016. Picture taken September 6, 2016. REUTERS/Charles Platiau

Democratic presidential candidate Hillary Clinton speaks during a campaign event with Vice-President Joe Biden in Scranton, Pennsylvania, August 15, 2016. REUTERS/Charles Mostoller 

People line up to try to buy staple food in a local supermarket, next to a sign that reads "The line starts here", in Caracas, Venezuela August 15, 2016. REUTERS/Marco Bello 

A truck takes a detour through a flooded street in Greenwell Springs, Louisiana, U.S., August 14, 2016. REUTERS/Jeffrey Dubinsky 

A note left on the podium for Republican presidential nominee Donald Trump directing him to the ropeline is pictured following a campaign rally in Cedar Rapids, Iowa, U.S., July 28, 2016. REUTERS/Carlo Allegri 

Texas delegate Kim Frederick poses for a photograph at the Democratic National Convention in Philadelphia, Pennsylvania, United States July 27, 2016. Frederick's message to the presidential nominee is: "[I want] more positivity uniting this country." REUTERS/Jim Young SEARCH "DELEGATES CONVENTIONS" FOR THIS STORY. SEARCH "THE WIDER IMAGE" FOR ALL STORIES 

A member of the Orange Order Parade looks on as they are stopped at a 15 foot deep temporary blockade put in place by the police in the Ardoyne area which an interface between the Catholic and Protestant communities during the annual Twelfth of July Orange Order Parade in Belfast, Northern Ireland, July 12, 2016. REUTERS/Clodagh Kilcoyne 

Britain Tennis - Wimbledon - All England Lawn Tennis & Croquet Club, Wimbledon, England - 3/7/16 General view outside courts REUTERS/Toby Melville 

A woman carries an umbrella past a pub being used as a polling station for the Referendum on the European Union in west London, Britain, June 23, 2016. REUTERS/Toby Melville

Nigel Farage, the leader of the United Kingdom Independence Party (UKIP), arrives to vote in the EU referendum, at a polling station in Biggin Hill, Britain June 23, 2016. REUTERS/Dylan Martinez

Nigel Farage, the leader of the United Kingdom Independence Party (UKIP), votes in the EU referendum, at a polling station in Biggin Hill, Britain June 23, 2016. REUTERS/Dylan Martinez TPX IMAGES OF THE DAY

Nigel Farage, the leader of the United Kingdom Independence Party (UKIP), leaves after voting in the EU referendum, at a polling station in Biggin Hill, Britain June 23, 2016. REUTERS/Dylan Martinez

Nigel Farage, the leader of the United Kingdom Independence Party (UKIP), leaves after voting in the EU referendum, at a polling station in Biggin Hill, Britain June 23, 2016. REUTERS/Dylan Martinez

Nigel Farage, the leader of the United Kingdom Independence Party (UKIP), leaves after voting in the EU referendum, at a polling station in Biggin Hill, Britain June 23, 2016. REUTERS/Dylan Martinez

Nigel Farage, the leader of the United Kingdom Independence Party (UKIP), leaves after voting in the EU referendum, at a polling station in Biggin Hill, Britain June 23, 2016. REUTERS/Dylan Martinez

Nigel Farage, the leader of the United Kingdom Independence Party (UKIP), arrives to vote in the EU referendum, at a polling station in Biggin Hill, Britain June 23, 2016. REUTERS/Dylan Martinez

Nigel Farage, the leader of the United Kingdom Independence Party (UKIP), arrives to vote in the EU referendum, at a polling station in Biggin Hill, Britain June 23, 2016. REUTERS/Dylan Martinez

Nigel Farage, the leader of the United Kingdom Independence Party (UKIP), arrives to vote in the EU referendum, at a polling station in Biggin Hill, Britain June 23, 2016. REUTERS/Dylan Martinez

A man leaves after voting in the EU referendum, at a polling station in Biggin Hill, Britain June 23, 2016. REUTERS/Dylan Martinez

A man arrives to vote with his dog at a polling station for the Referendum on the European Union in west London, Britain, June 23, 2016. REUTERS/Toby Melville

A man cycles past a polling station for the Referendum on the European Union in west London, Britain, June 23, 2016. REUTERS/Toby Melville

A policeman stands outside a polling station in Biggin Hill, Britain June 23, 2016. REUTERS/Dylan Martinez

A dog waits for its owner outside a polling station for the Referendum on the European Union in west London, Britain, June 23, 2016. REUTERS/Toby Melville

A woman carries an umbrella past a pub being used as a polling station for the Referendum on the European Union in west London, Britain, June 23, 2016. REUTERS/Toby Melville TPX IMAGES OF THE DAY 

A man carries an umbrella outside a polling station for the Referendum on the European Union in west London, Britain, June 23, 2016. REUTERS/Toby Melville

A man carries an umbrella outside a polling station for the Referendum on the European Union in west London, Britain, June 23, 2016. REUTERS/Toby Melville

A dog waits for its owner outside a polling station for the Referendum on the European Union in west London, Britain, June 23, 2016. REUTERS/Toby Melville

A sign points to a pub being used as a polling station for the Referendum on the European Union in west London, Britain, June 23, 2016. REUTERS/Toby Melville

Women walk past a pub being used as a polling station for the Referendum on the European Union in west London, Britain, June 23, 2016. REUTERS/Toby Melville

A sign points to the underground parking of German Uniper SE outside utility's firm headquarters previously used by German utility giant E.ON in Duesseldorf Germany, June 8, 2016. REUTERS/Wolfgang Rattay

A volunteer holds a sign directing supporters towards the entrance of a rally where Democratic U.S. presidential candidate Hillary Clinton will appear to celebrate her California primary night in the Brooklyn borough of New York, U.S., June 7, 2016. REUTERS/Lucas Jackson 

U.S. Democratic presidential candidate Hillary Clinton waits to go on stage at the Union of Carpenters and Millwrights Training Center in Louisville, Kentucky, U.S., May 15, 2016. REUTERS/Aaron P. Bernstein 

Supporters wait for Democratic U.S. presidential candidate Hillary Clinton at her five state primary night rally in Philadelphia, Pennsylvania, U.S., April 26, 2016. REUTERS/Dominick Reuter 

A sign with the word "bees" indicates the way to the venue of the presentation to the media of tens of thousands honeybees permanently placed in a courtyard of a lower house of the German parliament Bundestag office building in Berlin, Germany, April 25, 2016. REUTERS/Fabrizio Bensch 

Runners take part in the Vienna City Marathon in Vienna, Austria, April 10, 2016. Picture taken with long exposure. REUTERS/Heinz-Peter Bader 

Runners take part in the Vienna City Marathon in Vienna, Austria, April 10, 2016. Picture taken with long exposure. REUTERS/Heinz-Peter Bader 

Supporters of U.S. Democratic presidential candidate Hillary Clinton hold a sign as she speaks at a campaign rally in Cohoes, New York, April 4, 2016. REUTERS/Mike Segar 

A directional sign post is seen at the Neutral Nations Supervisory Commissions (NNSC) headquarters near the truce village of Panmunjom, South Korea, March 30, 2016. REUTERS/Kim Hong-Ji 

Indigenous men from the Erikbaktsa tribe watch the bow-and-arrow competition at the first World Games for Indigenous Peoples in Palmas, Brazil, October 26, 2015. REUTERS/Ueslei Marcelino 

A tyre air gun is seen on the ground during the first free practice session for the Italian F1 Grand Prix in Monza September 4, 2015. REUTERS/Max Rossi

A portion of a historical collection of over 2325 broadhead points is seen on display at North American bow-hunting club Pope & Young's museum in Chatfield, Minnesota July 31, 2015. The Pope & Young Club, a Minnesota-based bowhunting and conservation organization that includes dentist Walter Palmer among its members, said it was looking into his hunt which killed a locally famous lion in Zimbabwe, though it focuses only on North American big game. The club said its ethical code calls for fair chase of animals, which does not allow the hunter an unfair advantage, and does not condone violations of that code. REUTERS/Eric Miller 

A man waits next to his car to get on a ferry to Morocco at the southern Spanish port of Algeciras July 31, 2015. Each year, thousands of Moroccan families returning from their vacation in Europe wait long hours at the Spanish port to get on a ferry that will take them back to Morocco. REUTERS/Jon Nazca 

A D.R. Horton home building project is pictured in San Marcos, California July 28, 2015. D.R. Horton Inc's quarterly profit handily beat estimates and the No.1 U.S. homebuilder said orders rose 22 percent, indicating that a recovery in the housing market was gaining steam. REUTERS/Mike Blake 

EDITORIAL USE ONLY - NO COMMERCIAL OR BOOK SALES. A trading board showing the last foreign exchange fixing before Greece joined the Eurozone is displayed at the Museum of the Bank of Greece in Athens June 11, 2015. The International Monetary Fund dramatically raised the stakes in Greece's stalled debt talks on Thursday, announcing that its delegation had broken off negotiations in Brussels and flown home because of major differences with Athens. REUTERS/Yannis Behrakis TPX IMAGES OF THE DAY