People enjoying the races on a wet day at Chester Racecourse on May 12, 2017 in Chester, England. (Photo by Alan Crowhurst/Getty Images)

An Iraqi military vehicle passes displaced Iraqi boys returning to their homes in West Mosul's Oreibi neighbourhood after government forces retook control of the area from the Islamic State (IS) group during the ongoing offensive against the jihadists on May 21, 2017. (Photo by Ahmad Al-Rubaye/AFP Photo)

A demonstrator throw a firebomb during clashes with Turkish riot police officers in Istanbul, Turkey, Friday, May 1, 2015. The government assigned 30,000 police officers backed by helicopters as workers and demonstrators determined to defy a government ban, tried to march to iconic Taksim Square, where 35 people were killed during May Day celebration in 1977. (Photo by Emrah Gurel/AP Photo)

A four-legged robot dog called SPOT patrols a park as it undergoes testing to be deployed as a safe distancing ambassador, following the coronavirus disease (COVID-19) outbreak, in Singapore on May 8, 2020. (Photo by Edgar Su/Reuters)

Guests watch “Trolls World Tour”, in the rain at the Four Brothers Drive In Theatre amid the coronavirus pandemic, Friday, May 15, 2020, in Amenia, N.Y. (Photo by John Minchillo/AP Photo)

Shaolin martial arts students perform Kung Fu suspended on wires in a rehearsal for a live-action night show in Zhengzhou, Henan province, China on April 28, 2018. (Photo by Reuters/China Stringer Network)

A woman walks past servicemen of the self-proclaimed Donetsk People's Republic (DNR), who take part in a rehearsal for the Victory Day parade in Donetsk, Ukraine on May 3, 2018. (Photo by Alexander Ermochenko/Reuters)

A cosplayer poses for a photograph during the Tokyo Rainbow Pride Parade on May 6, 2018 in Tokyo, Japan. The LGBT community and supporters marched down Shibuya and Harajuku areas on the final day of the Tokyo Rainbow Pride 2018 event. (Photo by Tomohiro Ohsumi/Getty Images)