Queen Mathilde of Belgium and King Philippe - Filip of Belgium visit the exhibition on science and culture 'Science et culture au Palais', at the Royal Palace in Brussels, on July 20, 2016 on the opening day of the exhibition. / AFP PHOTO / Belga / THIERRY ROGE / Belgium OUTTHIERRY ROGE/AFP/Getty Images

CLEVELAND, OH - JULY 20: Stephen K. Bannon looks at his computer to see who will be the next caller he will talk to while hosting Brietbart News Daily on SiriusXM Patriot at Quicken Loans Arena on July 20, 2016 in Cleveland, Ohio. (Photo by Kirk Irwin/Getty Images for SiriusXM)

CLEVELAND, OH - JULY 20: Stephen K. Bannon looks at his computer to see who will be the next caller he will talk to while hosting Brietbart News Daily on SiriusXM Patriot at Quicken Loans Arena on July 20, 2016 in Cleveland, Ohio. (Photo by Kirk Irwin/Getty Images for SiriusXM)

(FILES) This file photo taken on September 11, 2013 shows the logo of social networking website 'Twitter' is displayed on a computer screen in London. Twitter and the National Basketball Association announced a deal July 19, 2016 to stream live content, but not games, to users of the social media platform. The deal will deliver a weekly NBA pregame show with "first-of-its-kind elements created specifically for integration with Twitter conversation," according to a joint statement. / AFP PHOTO / LEON NEALLEON NEAL/AFP/Getty Images

A technician works on a computer at the control room of the Matebe dam on July 18, 2016, in Matebe. The Matebe dam is a project from the Virunga Alliance for a sustainable development in the surroundings of the Virunga National Park. / AFP PHOTO / Eduardo SoterasEDUARDO SOTERAS/AFP/Getty Images

BERKELEY, CA - JULY 18: A man is seen wearing a 'Stop the Hate' hat during a vigil in honor of Nicolas Leslie, a UC Berkeley student killed in last week's truck attack in Nice, France, on July 18, 2016 at Sproul Plaza in Berkeley, California. Leslie, an environmental sciences major, was part of the university's study-abroad program in Nice during the attack. (Photo by Stephen Lam/Getty Images)

BERKELEY, CA - JULY 18: A man raises his fist during a vigil in honor of Nicolas Leslie, a student killed in last week's truck attack in Nice, France, on July 18, 2016 at Sproul Plaza in Berkeley, California. Leslie, an environmental sciences major, was part of the university's study-abroad program in Nice during the attack. (Photo by Stephen Lam/Getty Images)

BERKELEY, CA - JULY 18: People write on a sheet of paper in Sproul Plaza during a vigil in honor of Nicolas Leslie, a UC Berkeley student killed in last week's truck attack in Nice, France, on July 18, 2016 at Sproul Plaza in Berkeley, California. Leslie, an environmental sciences major, was part of the university's study-abroad program in Nice during the attack. (Photo by Stephen Lam/Getty Images)