Children wave Vietnamese and American flags while waiting for arrival of U.S. President Barack Obama (not pictured) before a welcoming ceremony at the Presidential Palace in Hanoi, Vietnam May 23, 2016. (Photo by Reuters/Kham)

A hungry cow smiles for the camera in Salzburg, Austria. One of a series of funny animal mugshots taken by Chanel Cartell and Stevo Dirnberger during their travels around the globe. (Photo by Chanel Cartell/Stevo Dirnberger/Rex Features/Shutterstock)

Cloud inversion taken at Sunrise in Mam Tor, Derbyshire, UK on August 30, 2016. (Photo by David Zdanowicz/REX Shutterstock)

David Nickerson, 24, rides a wave dressed as Mrs Doubtfire during the 7th annual ZJ Boarding House Haunted Heats Halloween surf contest. (Photo by Lucy Nicholson/Reuters)

Runners gather at the start line for the annual “Santa Speedo Run”, a charity race through the streets of the Back Bay neighborhood of Boston. (Photo by Gretchen Ertl/Reuters)

British model Jean Shrimpton at London Airport (now Heathrow), 5th June 1967. (Photo by Dove/Express/Getty Images)

Kiki Layne attends the 24th annual Critics' Choice Awards at Barker Hangar on January 13, 2019 in Santa Monica, California. (Photo by Rob Latour/Rex Features/Shutterstock)

Florence Welch of Florence And The Machine performs at Spark Arena on January 30, 2019 in Auckland, New Zealand. (Photo by Dave Simpson/WireImage)