Colorado Gov. John Hickenlooper shows off his socks--one with Democratic presidential candidate Bernie Sanders and the other with Republican candidate Donald Trump – before entering his former brewpub for a book signing event to mark the release of his autobiography Thursday, May 26, 2016, in Denver. Hickenlooper, who is term-limited, is doing book talk rounds this week, reviving speculation that he is positioning himself to join Hillary Clinton's presidential campaign ticket. (Photo by David Zalubowski/AP Photo)

A man transports passengers on an improvised motorized rickshaw during heavy rains in Agartala, India, April 20, 2018. (Photo by Jayanta Dey/Reuters)

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)

People attend the 49th annual New York City Gay Pride Parade in New York, New York, USA on 24 June 2018. (Photo by Erik Pendzich/Rex Features/Shutterstock)

Pallas' s cat kittens with theit mother in an enclosure at the Novosibirsk Zoo, Novosibirsk, Russia on July 11, 2018. Pallas' s cat, also known as manul, is a small wild cat native to montane steppes of the Central Asia and listed as an endangered species. (Photo by Kirill Kukhmar/TASS)

Women lie in the sun in Domino Park as high temperatures hit the region in Brooklyn, New York, U.S., August 29, 2018. (Photo by Andrew Kelly/Reuters)

Girls sits on a bench during summer at the Central Park in New York, United States, 2011. (Photo by An Rong Xu)

Daniel Cheong, a dog behaviorist and trainer, steps over a leash as he walks a pack of dogs in Arlington, Va. on November 13, 2018. (Photo by Ricky Carioti/The Washington Post)