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)

Children play football in front of an abandoned train compartment next to a railway track in Dhaka, in this May 29, 2014 file photo. (Photo by Andrew Biraj/Reuters)

Gunfire erupted at a Denver pot celebration Saturday, injuring two people and scattering a crowd of thousands who had gathered for the first 4/20 counterculture holiday since the state legalized marijuana... Photo: A woman smokes a large marijuana joint at the Vancouver Art Gallery during the annual 4/20 day, which promotes the use of marijuana, in Vancouver, British Columbia April 20, 2013. (Photo by Ben Nelms/Reuters)

1st prize in the People Observed Portraits Stories category. Carla Kogelman, the Netherlands. The photo shows Hannah and Alena, two sisters living in the rural village of Merkenbrechts, Austria. (Photo by Carla Kogelman/World Press Photo)

Pedestrians wear masks as smoke and haze from bushfires in New South Wales blankets the CBD in Sydney, Australia, 10 December 2019. The New South Wales environment department says visibility across east and southwest Sydney was at a “hazardous” level on Tuesday morning, while air quality was poor in southwest Sydney and hazardous in northwest Sydney. (Photo by Steven Saphore/EPA/EFE)

Fox cubs venture out from their den under a popular boardwalk alongside Lake Ontario during the global outbreak of the coronavirus disease (COVID-19), in Toronto, Ontario, Canada on April 22, 2020. (Photo by Carlos Osorio/Reuters)

The body of one of several U.S. soldiers who were executed after being captured by North Korean troops just south of Seoul in early July 1950. (Photo by AP Photo)

Cameroonian model Venance Chiepodeu also known as Miss Cameroon arrives at Spring Studios for the LaQuan Smith's Dinner during fashion week in New York City on September 16, 2020. (Photo by Gabriele Holtermann/Sipa USA)