Soldiers stand in line outside portable toilets during a military parade to celebrate the 206th anniversary of Colombia's independence in Bogota, Colombia, July 20, 2016. (Photo by John Vizcaino/Reuters)

2016 Rio Olympics, Artistic gymnastics, Women's Training, Rio Athletes Park, Rio De Janeiro, Brazil on July 27, 2016. A gymnast from Russia trains. (Photo by Ivan Alvarado/Reuters)

A tank's barrel is seen on the course of the Tank Biathlon competition during the International Army Games 2016 in Alabino, outside Moscow, Russia, July 30, 2016. (Photo by Maxim Zmeyev/Reuters)

2016 Rio Olympics, Weightlifting, Final, Women's 69kg, Riocentro, Pavilion 2, Rio de Janeiro, Brazil on August 10, 2016. Leidy Solis (COL) of Colombia competes. (Photo by Stoyan Nenov/Reuters)

Two holidaymakers amuse themselves with a porter's trolley whilst waiting for their train at Euston Station, London, 5th August 1939. (Photo by A. J. O'Brien/Fox Photos/Getty Images)

In this handout photograph received from Sumukha J.N on December 15, 2016, the newly-discovered spider Eriovixia Gryffindori sits on a leaf in the Kans in India's Western Ghats. (Photo by Sumukha J.N./AFP Photo)

A masked reveller poses near Saint Mark's Square during the Venetian Carnival in Venice January 31, 2015. (Photo by Stefano Rellandini/Reuters)

Ana Ivanovic of Serbia plays a backhand return to Maria Sharapova of Russia during their women's singles final match at the Brisbane International tennis tournament in Brisbane, January 10, 2015. (Photo by Jason Reed/Reuters)