Palestinian boy Mohammad Shanty, who suffers from cystic fibrosis, sits next to his mother after receiving oxygen therapy during a power cut in their family house, which is equipped with a backup battery-powered system, in Gaza City July 2, 2017. Picture taken July 2, 2017. REUTERS/Mohammed Salem

Mother of Youssef Abdullah, one of at least 22 Egyptians found dead earlier this month, perishing from heat and starvation after trekking the Libyan desert by foot, reacts in the village of Tarfa al-Kom in Minya province, Egypt, July 12, 2017. Picture taken July 12, 2017. REUTERS/Mohamed Abd El Ghany

Medical practitioners attend to a cholera patient inside a special ward at the Kenyatta National Hospital in Nairobi, Kenya July 19, 2017. REUTERS/Thomas Mukoya

A journalist takes a photograph of a South Korean soldier standing guard at the truce village of Panmunjom, South Korea July 19, 2017. REUTERS/Kim Hong-Ji

Prince George arrives at Tegel airport in Berlin, Germany, July 19, 2017. REUTERS/Fabrizio Bensch

A man walks past the graves of soldiers killed in the 1974 Turkish invasion of Cyprus at the Tymvos Macedonitissas military cemetery in Nicosia, Cyprus July 19, 2017. REUTERS/Yiannis Kourtoglou

U.S. President Donald Trump speaks during a lunch meeting with Senate Republicans to discuss healthcare at the White House in Washington, U.S., July 19, 2017. From left are U.S. Senators Shelley Moore Capito (R-WV), Dean Heller (R-NV), Tim Scott (R-SC) and Lisa Murkowski (R-AK). REUTERS/Kevin Lamarque

Senate Majority Leader Mitch McConnell looks down as U.S. President Donald Trump speaks during a meeting with Senate Republicans to discuss healthcare at the White House in Washington, U.S., July 19, 2017. REUTERS/Kevin Lamarque

Golf - The 146th Open Championship - Royal Birkdale - Southport, Britain - July 19, 2017 USA’s Jordan Spieth catches golf balls during a practice round TPX IMAGES OF THE DAY REUTERS/Paul Childs

Prince William, the Duke of Cambridge and his wife Catherine, The Duchess of Cambridge, visit the Holocaust Memorial in Berlin, Germany July 19, 2017. REUTERS/Hannibal Hanschke

Synchro - 17th FINA World Championships - Women Team Free Preliminary - Budapest, Hungary - July 19, 2017 - Team Ukraine competes. REUTERS/Michael Dalder

Flames from the Detwiler fire burn on a hill overlooking the town of Mariposa, California, U.S., July 18, 2017. Picture taken July 18, 2017. REUTERS/Stephen Lam

A demonstrator is detained by police officers after shouting slogans against abortion inside the Chilean congress during a session legislating a draft law which seeks to ease the country's strict abortion ban, in Valparaiso, Chile July 18, 2017. REUTERS/Rodrigo Garrido

Belgian researcher Jeroen Schuermans holds a human brain, part of a collection of more than 3,000 brains that could provide insight into psychiatric diseases, at the psychiatric hospital in Duffel, Belgium, July 19, 2017. REUTERS/Yves Herman

A chimney stands amidst remains of a home destroyed by the Detwiler fire in Mariposa, California U.S. July 19, 2017. REUTERS/Stephen Lam

Men swim in the Euphrates river to cool off in Najaf, Iraq July 19, 2017. REUTERS/Alaa Al-Marjani

A two-month-old unnamed male baby elephant chases a bird at the Africam Safari Zoo in Puebla, Mexico, July 19, 2017. REUTERS/Edgard Garrido

Wes Gerwien, 28, looks out a window of his family home that was covered in fire retardant in Cache Creek, British Columbia, Canada July 18, 2017. Residents of the town were forced to evacuate 11 days ago and can now return to their homes. REUTERS/Ben Nelms

Diving – 17th FINA World Aquatics Championships – 3m Springboard Men semifinal – Budapest, Hungary – July 19, 2017 – Matthieu Rosset of France competes. REUTERS/Stefan Wermuth

A Crocodile that was captured from a lagoon and temporarily kept in a zoo, is being caught in order to be transported and released in a national park, in Abidjan, Ivory Coast July 14, 2017. Picture taken July 14, 2017. REUTERS/Luc Gnago

A member of a sniper force loyal to the Houthi rebels takes part in a military parade at the Tahrir Square in downtown Sanaa, Yemen July 19, 2017. REUTERS/Khaled Abdullah

The signs, which read "Cristiano Ronaldo" (L) and "Messi", are on display outside a soccer stadium at an amusement park, made of straw and erected to attract customers, on the territory of the "Ponomaryovo" farming enterprise cultivating melons, watermelons and pumpkins in the settlement of Krasnoye in Stavropol region, Russia July 19, 2017. REUTERS/Eduard Korniyenko

Demonstrators protest against the Grenfell Tower fire outside a Kensington and Chelsea Council meeting at Kensington Town Hall in London, Britain July 19, 2017. REUTERS/Neil Hall