Senator Barack Obama (D-IL) (R) stands in front of Senator Hillary Clinton (D-NY) as they arrive for U.S. President George W. Bush's annual State of the Union speech to a joint session of Congress at the U.S. Capitol in Washington in this January 23, 2007 file photo. Hillary Clinton announced her second run for the presidency on April 12, 2015 starting her campaign as the Democrats' best hope of fending off a crowded field of lesser-known Republican rivals and retaining the White House. (Photo by Larry Downing/Reuters)

People line up to pay inside a Makro supermarket in Caracas, January 9, 2015. Venezuela's socialist government decreed an “economic emergency” on Friday that will expand its powers and published the first data in a year that shows the depth of a recession fueled by low oil prices and a sputtering state-led model. (Photo by Jorge Silva/Reuters)

Ngorongoro Crater (Tanzania). At 610m deep and 260 sq km, this is the largest unflooded caldera in the world. A blue-green vision from above it's a haven for engangered wildlife and Maasai livestock. The crater was formed three million years ago when a giant volcano, which could have been as high as Kilimanjaro, exploded and collapsed. The caldera formed the concentric fractures in the crust cracked down to a magma reservoir deep underground. (Photo by John Bryant/Getty Images)

A motorcyclist ferries a pillion rider sitting on goods in Phnom Penh on June 6, 2017. (Photo by Tang Chhin Sothy/AFP Photo)

Makeup artist He Yuhong, also known as “Yuya”, checks herself in the mirror during a photo shoot following her transformation into the “Girl with a Pearl Earring”, the 17th century oil painting by Dutch painter Johannes Vermeer, at her house in Chongqing, China on August 14, 2018. (Photo by Thomas Suen/Reuters)

A Pakistan fan poses for a photo during the Group Stage match of the ICC Cricket World Cup 2019 between Australia and Pakistan at The County Ground on June 12, 2019 in Taunton, England. (Photo by Alex Davidson/Getty Images)

Belle Hassan is seen attending Lipstick and Champagne – party at STK on August 29, 2019 in London, England. (Photo by Jamie Lorriman/The Sun)

A woman in yukata, casual summer kimono, poses for a photo at Fushimi Inari Taisha in Kyoto, Japan on October 2, 2019. (Photo by Matthew Childs/Reuters)