Swans paddle on Loch Faskally, Pitlochry, Scotland, Britain October 26, 2019. REUTERS/Russell Cheyne

Los Angeles County fire tender is seen during wind-driven wildfire fire in Sylmar, California, U.S., October 10, 2019. REUTERS/ Gene Blevins

A heart-shaped Chinese flag installation ahead of the 70th founding anniversary of People's Republic of China is seen on a street in Shanghai, China, September 26, 2019. Picture taken with a slow shutter speed and a zoom effect. REUTERS/Aly Song

A heart-shaped Chinese flag installation ahead of the 70th founding anniversary of People's Republic of China is seen on a street in Shanghai, China September 26, 2019. Picture taken with a slow shutter speed and a zoom effect. REUTERS/Aly Song

A heart-shaped Chinese flag installation ahead of the 70th founding anniversary of People's Republic of China is seen on a street in Shanghai, China, September 26, 2019. Picture taken with a slow shutter speed and a zoom effect. REUTERS/Aly Song

Two green sea turtles touch heads at the Israeli Sea Turtle Rescue Center, in Mikhmoret north of Tel Aviv, Israel September 23, 2019. Picture taken September 23, 2019. REUTERS/Amir Cohen

Newly-hatched baby sea turtles make their way into the Mediterranean Sea for the first time, as part of the Israeli Sea Turtle Rescue Center's conservation programme, at a beach near Mikhmoret north of Tel Aviv, Israel September 9, 2019. Picture taken September 9, 2019. REUTERS/Amir Cohen

A newly-hatched baby sea turtle makes its way into the Mediterranean Sea for the first time, as part of the Israeli Sea Turtle Rescue Center's conservation programme, at a beach near Mikhmoret north of Tel Aviv, Israel September 9, 2019. Picture taken September 9, 2019. REUTERS/Amir Cohen

A newly-hatched baby sea turtle makes its way into the Mediterranean Sea for the first time, as part of the Israeli Sea Turtle Rescue Center's conservation programme, at a beach near Mikhmoret north of Tel Aviv, Israel September 9, 2019. Picture taken September 9, 2019. REUTERS/Amir Cohen

A woman paddles on a stand-up board during sunrise in a beach in Larnaca, Cyprus September 15, 2019. REUTERS/Yiannis Kourtoglou

People paddle on a stand-up board during sunrise in a beach in Larnaca, Cyprus September 15, 2019. REUTERS/Yiannis Kourtoglou

People paddle on a stand-up board during sunrise in a beach in Larnaca, Cyprus September 15, 2019. REUTERS/Yiannis Kourtoglou

Britain's Prime Minister Boris Johnson speaks to apprentices accompanied by Britain's Defence Secretary Ben Wallace as he visits the NLV Pharos, a lighthouse tender moored on the river Thames to mark London International Shipping Week in London, Britain September 12, 2019. Daniel Leal-Olivas/Pool via REUTERS

Britain's Prime Minister Boris Johnson takes part in an activity with school children as he visits the NLV Pharos, a lighthouse tender moored on the river Thames to mark London International Shipping Week in London, Britain September 12, 2019. Daniel Leal-Olivas/Pool via REUTERS

Britain's Prime Minister Boris Johnson visits the NLV Pharos, a lighthouse tender moored on the river Thames to mark London International Shipping Week in London, Britain September 12, 2019. Daniel Leal-Olivas/Pool via REUTERS

Britain's Prime Minister Boris Johnson takes part in an activity with school children as he visits the NLV Pharos, a lighthouse tender moored on the river Thames to mark London International Shipping Week in London, Britain September 12, 2019. Daniel Leal-Olivas/Pool via REUTERS

Britain's Prime Minister Boris Johnson takes part in an activity with school children as he visits the NLV Pharos, a lighthouse tender moored on the river Thames to mark London International Shipping Week in London, Britain September 12, 2019. Daniel Leal-Olivas/Pool via REUTERS

Britain's Prime Minister Boris Johnson takes part in an activity with school children as he visits the NLV Pharos, a lighthouse tender moored on the river Thames to mark London International Shipping Week in London, Britain September 12, 2019. Daniel Leal-Olivas/Pool via REUTERS

Britain's Prime Minister Boris Johnson takes part in an activity with school children as he visits the NLV Pharos, a lighthouse tender moored on the river Thames to mark London International Shipping Week in London, Britain September 12, 2019. Daniel Leal-Olivas/Pool via REUTERS

Britain's Prime Minister Boris Johnson takes part in an activity with school children as he visits the NLV Pharos, a lighthouse tender moored on the river Thames to mark London International Shipping Week in London, Britain September 12, 2019. Daniel Leal-Olivas/Pool via REUTERS

Britain's Prime Minister Boris Johnson takes part in an activity with school children as he visits the NLV Pharos, a lighthouse tender moored on the river Thames to mark London International Shipping Week in London, Britain September 12, 2019. Daniel Leal-Olivas/Pool via REUTERS

Britain's Prime Minister Boris Johnson takes part in an activity with school children as he visits the NLV Pharos, a lighthouse tender moored on the river Thames to mark London International Shipping Week in London, Britain September 12, 2019. Daniel Leal-Olivas/Pool via REUTERS

Britain's Prime Minister Boris Johnson speaks to apprentices as he visits the NLV Pharos, a lighthouse tender moored on the river Thames to mark London International Shipping Week in London, Britain September 12, 2019. Daniel Leal-Olivas/Pool via REUTERS

Britain's Prime Minister Boris Johnson visits the NLV Pharos, a lighthouse tender moored on the river Thames to mark London International Shipping Week in London, Britain September 12, 2019. Daniel Leal-Olivas/Pool via REUTERS

Britain's Prime Minister Boris Johnson speaks to apprentices as he visits the NLV Pharos, a lighthouse tender moored on the river Thames to mark London International Shipping Week in London, Britain September 12, 2019. Daniel Leal-Olivas/Pool via REUTERS

Britain's Prime Minister Boris Johnson speaks to apprentices as he visits the NLV Pharos, a lighthouse tender moored on the river Thames to mark London International Shipping Week in London, Britain September 12, 2019. Daniel Leal-Olivas/Pool via REUTERS

Britain's Prime Minister Boris Johnson speaks to apprentices as he visits the NLV Pharos, a lighthouse tender moored on the river Thames to mark London International Shipping Week in London, Britain September 12, 2019. Daniel Leal-Olivas/Pool via REUTERS

Britain's Prime Minister Boris Johnson speaks to apprentices as he visits the NLV Pharos, a lighthouse tender moored on the river Thames to mark London International Shipping Week in London, Britain September 12, 2019. Daniel Leal-Olivas/Pool via REUTERS

Britain's Prime Minister Boris Johnson speaks to apprentices as he visits the NLV Pharos, a lighthouse tender moored on the river Thames to mark London International Shipping Week in London, Britain September 12, 2019. Daniel Leal-Olivas/Pool via REUTERS

Britain's Prime Minister Boris Johnson speaks to apprentices as he visits the NLV Pharos, a lighthouse tender moored on the river Thames to mark London International Shipping Week in London, Britain September 12, 2019. Daniel Leal-Olivas/Pool via REUTERS

Britain's Prime Minister Boris Johnson speaks to apprentices as he visits the NLV Pharos, a lighthouse tender moored on the river Thames to mark London International Shipping Week in London, Britain September 12, 2019. Daniel Leal-Olivas/Pool via REUTERS

Britain's Prime Minister Boris Johnson speaks to apprentices as he visits the NLV Pharos, a lighthouse tender moored on the river Thames to mark London International Shipping Week in London, Britain September 12, 2019. Daniel Leal-Olivas/Pool via REUTERS

Britain's Prime Minister Boris Johnson visits the NLV Pharos, a lighthouse tender moored on the river Thames to mark London International Shipping Week in London, Britain September 12, 2019. Daniel Leal-Olivas/Pool via REUTERS

Britain's Prime Minister Boris Johnson speaks to apprentices as he visits the NLV Pharos, a lighthouse tender moored on the river Thames to mark London International Shipping Week in London, Britain September 12, 2019. Daniel Leal-Olivas/Pool via REUTERS

Britain's Prime Minister Boris Johnson visits the NLV Pharos, a lighthouse tender moored on the river Thames to mark London International Shipping Week in London, Britain September 12, 2019. Daniel Leal-Olivas/Pool via REUTERS

Britain's Prime Minister Boris Johnson visits the NLV Pharos, a lighthouse tender moored on the river Thames to mark London International Shipping Week in London, Britain September 12, 2019. Daniel Leal-Olivas/Pool via REUTERS

Britain's Prime Minister Boris Johnson visits the NLV Pharos, a lighthouse tender moored on the river Thames to mark London International Shipping Week in London, Britain September 12, 2019. Daniel Leal-Olivas/Pool via REUTERS

People ride a pedal boat on the Vltava River as the sun sets over the Prague Castle in Prague, Czech Republic, September 10, 2019. REUTERS/David W Cerny

People ride pedal boats on the Vltava River as the sun sets over the Prague Castle in Prague, Czech Republic, September 10, 2019. REUTERS/David W Cerny

A zebra rubs its head against another at London Zoo, London, Britain, August 22, 2019. REUTERS/Toby Melville

A Hindu devotee with hooks pierced into his back participates in a religious procession to celebrate Aadi Kiruthigai, a festival dedicated to Hindu god Murugan, in Chennai, India, July 28, 2019. REUTERS/P. Ravikumar TPX IMAGES OF THE DAY

Ducks are pictured at a farm in Jiaxiang county, Shandong province, China, July 16, 2019. Picture taken July 16, 2019. REUTERS/Jason Lee

Ducklings are seen at a farm in Jiaxiang county, Shandong province, China, July 16, 2019. Picture taken July 16, 2019. REUTERS/Jason Lee

People protect themselves from the sun with parasols while rowing in Central Park as a heatwave continues to affect the region in New York, U.S., July 21, 2019. REUTERS/Andrew Kelly

A general view of Fanore beach in evening light, Fanore, Ireland, July 7, 2019. REUTERS/Peter Cziborra

A baby hippo stands in water near its mother Mona at Dvur Kralove Zoo, Czech Republic, June 12, 2019. Picture taken June 12, 2019. REUTERS/David W Cerny

A baby hippo swims in a pond near its mother Mona at Dvur Kralove Zoo, Czech Republic, June 12, 2019. Picture taken June 12, 2019. REUTERS/David W Cerny

A couple walk in the Baltic Sea during sunset in Komarovo outside Saint Petersburg, Russia June 8, 2019. Picture taken June 8, 2019. REUTERS/ Maxim Shemetov

Pusha the cat, which adopted four orphaned baby squirrels and currently feeds and lives with them, lies at a local park of miniatures in Bakhchisaray, Crimea April 25, 2019. REUTERS/Alexey Pavlishak TPX IMAGES OF THE DAY

Pusha the cat, which adopted four bereaved baby squirrels and currently feeds and lives with them, lies at a local park of miniatures in Bakhchisaray, Crimea April 25, 2019. REUTERS/Alexey Pavlishak

A 10-day old baby western lowland gorilla in Dublin Zoo is seen clinging to its mother Kafi in Dublin, Ireland April 11, 2019. REUTERS/Clodagh Kilcoyne

A 10-day old baby western lowland gorilla in Dublin Zoo is seen held by its mother Kafi in Dublin, Ireland April 11, 2019. REUTERS/Clodagh Kilcoyne

A 10-day old baby western lowland gorilla in Dublin Zoo is seen held by its mother Kafi in Dublin, Ireland April 11, 2019. REUTERS/Clodagh Kilcoyne

A 10-day old baby western lowland gorilla in Dublin Zoo is seen clinging to its mother Kafi in Dublin, Ireland April 11, 2019. REUTERS/Clodagh Kilcoyne

A black-and-white colobus monkey holds its 11 days old infant at its enclosure in Schoenbrunn Zoo in Vienna, Austria April 10, 2019. REUTERS/Leonhard Foeger

A black-and-white colobus monkey holds its 11 days old infant at its enclosure in Schoenbrunn Zoo in Vienna, Austria April 10, 2019. REUTERS/Leonhard Foeger

A black-and-white colobus monkey holds its 11 days old infant at its enclosure in Schoenbrunn Zoo in Vienna, Austria April 10, 2019. REUTERS/Leonhard Foeger

Still image from video shows the Tender Buttons shop, named after a book of poems by Gertrude Stein, opened in 1964, on Manhattan's Upper East Side in New York City, U.S., on March 19, 2019. Image taken on March 19, 2019. REUTERS/Hussein Al Waaile

Still image from video shows the Tender Buttons shop, named after a book of poems by Gertrude Stein, opened in 1964, on Manhattan's Upper East Side in New York City, U.S., on March 19, 2019. Image taken on March 19, 2019. REUTERS/Hussein Al Waaile

Still image from video shows the store's walls lined with buttons from around the world at the Tender Buttons shop, named after a book of poems by Gertrude Stein, on Manhattan's Upper East Side in New York City, U.S., on March 19, 2019. Image taken on March 19, 2019. REUTERS/Hussein Al Waaile